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prof. RNDr. René Hudec, CSc.

Všechny publikace

Experimental astronomical observation using a lobster eye optics

  • DOI: 10.1002/asna.20230106
  • Odkaz: https://doi.org/10.1002/asna.20230106
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A lobster eye (LE) is a wide-field type of X-ray optics, which provides a large field of view at the expense of angular resolution. The optics presented in this paper are the LE optics in Schmidt arrangement made from glass sheets with golden reflective coatings. It was used as a scientific payload on the WRXR rocket experiment. Before the mission itself, the optics was tested on ground to obtain more information about its behavior. Part of these tests were several nights of observation at the Ondrejov observatory. We used the optics in combination with a CMOS camera to acquire images in visible light of various bright sources in the sky. In order to enable long-time exposures, the robotic mount of the BART telescope was used. The goal of this experiment was to confirm the focal length of the optics using a source at infinity, and to show how the optics, designed for X-ray observations, performs in visible light. This brief article describes the methods used for evaluation and presents and discusses the results obtained within the night observation experiment.

Soft X-ray observing the cosmic sources by the ESA–CAS satellite SMILE

  • DOI: 10.1016/j.jheap.2024.02.005
  • Odkaz: https://doi.org/10.1016/j.jheap.2024.02.005
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper describes the scientific potential of a Soft X-ray Imager (SXI) onboard the ESA–CAS satellite SMILE for investigating cosmic X-ray sources of various types. We show that this instrument, albeit designed for X-ray imaging of solar wind Charge eXchange of the magnetosheath and the cusps, is also essential for astrophysics because it is able to provide wide-field imaging of the sky in the soft X-ray region. Regarding sufficiently luminous X-ray sources with continuous spectra to be observable by the X-ray monitor MAXI/ISS to assess the object types and their light curves that are expected to be detected by SXI/SMILE, the compact sources accreting matter are promising targets for evaluating the possibilities of SXI. We assumed only the cosmic objects located in the planned fields to be observed by SXI. We used the 2–3 keV band flux of MAXI/ISS covering at least part of the expected band of the SXI/SMILE telescope. We used the data obtained by MAXI/ISS to assess the object types and their light curves expected to be detected by SXI/SMILE. We show the long-term activity of the examples of X-ray binary types located in this region. We present the typical features of such objects' activity on long timescales (e.g., outbursts and state transitions) and include physical interpretations of these phenomena. Furthermore, we discuss how SXI can contribute to this branch.

Testing of lobster-eye type telescopes with X-rays and visible light

  • Autoři: Döhring, T., Stieglitz, V., Friedrich, P., Burwitz, V., prof. RNDr. René Hudec, CSc.,
  • Publikace: EUV and X-ray Optics: Synergy between Laboratory and Space VIII 2023. Bellingham: SPIE, 2023.
  • Rok: 2023

CZEV502-AN M DWARF NEAR THE LEO TRIPLET WITH VERY STRONG FLARES

  • Autoři: Liska, J., prof. RNDr. René Hudec, CSc., Mikulasek, Z., Zejda, M.
  • Publikace: REVISTA MEXICANA DE ASTRONOMIA Y ASTROFISICA. 2022, 58(1), 155-168. ISSN 0185-1101.
  • Rok: 2022
  • DOI: 10.22201/ia.01851101p.2022.58.01.12
  • Odkaz: https://doi.org/10.22201/ia.01851101p.2022.58.01.12
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Discovery of flares in the M dwarf CzeV502 and our follow-up results are presented. We classify it as a dMe eruptive variable of UV Ceti type due to the X-ray activity, measured B -V of 1.5 mag, H alpha emission, and flares. Our monitoring revealed only one reliable and one suspected superflare in 58 nights (210 hrs). The strongest flare with Delta R = 1.5 mag (Delta B approximate to 6-8 mag) could have a total energy of 3E+34 erg. The ASAS-SN data may contain 4 events up to Delta V of 0.43 mag and 12.55 d periodicity corresponding to the rotation or possible binarity. Other brightenings in sky survey (ASAS-3, CRTS, NSVS, and KWS) are doubtful. No event was unveiled on the 1600 photographic plates. The upper rate limit of 1-2 superflares/1 640 hrs corresponds to activity several orders higher than for other M-dwarfs, especially, for the slow rotators. The low amplitude flares (Delta B < 0.5 mag) may be common (1 flare/4 hrs).

Directional-Sensitive X-ray/Gamma-ray Imager on Board the VZLUSAT-2 CubeSat for Wide Field-of-View Observation of GRBs in Low Earth Orbit

  • Autoři: Granja, C., prof. RNDr. René Hudec, CSc., Maršíková, V., Inneman, A., Pína, L.
  • Publikace: Universe. 2022, 8(4), ISSN 2218-1997.
  • Rok: 2022
  • DOI: 10.3390/universe8040241
  • Odkaz: https://doi.org/10.3390/universe8040241
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present a miniaturized and wide field-of-view X-ray and Gamma-ray imager consisting of a segmented 2D optics-collimator coupled to the high-sensitivity semiconductor pixel detector Timepix equipped with a high-Z sensor (CdTe 2000 mu m thick). The compact payload has been deployed in low-Earth orbit (LEO) onboard the 3U Cubesat VZLUSAT-2 which was launched on 13 January 2022. The instrument is designed to verify small spacecraft borne observation in open space of hard X-ray and Gamma-ray sources both of celestial and atmospheric origin. High-resolution spectral-sensitive X-ray and Gamma-ray images are provided with enhanced event discrimination and wide field-of-view up to 60 degrees. Description of the instrument together with response evaluation and tests in ground with well-defined sources are presented. The intended observational plan for in-orbit measurements is outlined along with astrophysical goals and issues.

GRB 190919B: Rapid optical rise explained as a flaring activity

  • DOI: 10.1051/0004-6361/202143010
  • Odkaz: https://doi.org/10.1051/0004-6361/202143010
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Following the detection of a long GRB 190919B by INTEGRAL (INTErnational Gamma-Ray Astrophysics Laboratory), we obtained an optical photometric sequence of its optical counterpart. The light curve of the optical emission exhibits an unusually steep rise similar to 100 s after the initial trigger. This behaviour is not expected from a 'canonical' GRB optical afterglow. As an explanation, we propose a scenario consisting of two superimposed flares: an optical flare originating from the inner engine activity followed by the hydrodynamic peak of an external shock. The inner-engine nature of the first pulse is supported by a marginal detection of flux in hard X-rays. The second pulse eventually concludes in a slow constant decay, which, as we show, follows the closure relations for a slow cooling plasma expanding into the constant interstellar medium and can be seen as an optical afterglow sensu stricto.

Perspectives of the LOBSTER-EYE monitor in the soft X-ray observing the Galactic center region

  • DOI: 10.1016/j.jheap.2022.06.001
  • Odkaz: https://doi.org/10.1016/j.jheap.2022.06.001
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We show the lobster-eye (LE) monitor's perspectives and observing plan based on a small LE telescope on a small (CubeSat-like) satellite platform. This instrument is important because it is able to provide wide-field X-ray imaging. We present the possibilities of monitoring the Galactic center region in the soft X-ray energy band. The reason is that many X-ray binaries, especially those with a low-mass lobe-filling secondary and mostly the neutron star accretor, concentrate in the bulge surrounding the center of our Galaxy. Several such binaries are expected to be present in our monitor's field of view (a square of about degrees). We show the long-term activity of the examples of X-ray binaries located in this region. We present the typical features of such objects' long-term X-ray activity (e.g., outbursts and state transitions) and discuss how the lobster-eye monitor can contribute. Observing in the soft X-ray band is the most promising because their X-ray intensity is the highest in this band.

Promise of persistent multi-messenger astronomy with the blazar oj 287

  • Autoři: Valtonen, M.J., Dey, L., Gopakumar, A., Zola, S., prof. RNDr. René Hudec, CSc.,
  • Publikace: Galaxies. 2022, 10(1), ISSN 2075-4434.
  • Rok: 2022
  • DOI: 10.3390/galaxies10010001
  • Odkaz: https://doi.org/10.3390/galaxies10010001
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Successful observations of the seven predicted bremsstrahlung flares from the unique bright blazar OJ 287 firmly point to the presence of a nanohertz gravitational wave (GW) emitting supermassive black hole (SMBH) binary central engine. We present arguments for the continued monitoring of the source in several electromagnetic windows to firmly establish various details of the SMBH binary central engine description for OJ 287. In this article, we explore what more can be known about this system, particularly with regard to accretion and outflows from its two accretion disks. We mainly concentrate on the expected impact of the secondary black hole on the disk of the primary on December 3, 2021, and the resulting electromagnetic signals in the following years. We also predict the times of exceptional fades and outline their usefulness in the study of the host galaxy. A spectral survey has been carried out, and spectral lines from the secondary were searched for but not found. The jet of the secondary has been studied and proposals to discover it in future VLBI observations are mentioned. In conclusion, the binary black hole model explains a large number of observations of different kinds in OJ 287. Carefully timed future observations will be able to provide further details of its central engine. Such multi-wavelength and multidisciplinary efforts will be required to pursue multi-messenger nanohertz GW astronomy with OJ 287 in the coming decades.

Small Spacecraft Payload Study for X-ray Astrophysics including GRB Science

  • DOI: 10.3390/universe8030144
  • Odkaz: https://doi.org/10.3390/universe8030144
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper presents microsatellite spacecraft payload study for prompt observation of transient astrophysical objects in X-ray energy range. By combining telescope concepts and miniaturized detectors, the small spacecraft will be able to probe the X-ray temporal emissions of bright events such as Gamma-Ray Bursts (GRBs), X-ray transients or the electromagnetic counterparts of Gravitational Wave Events (GWEs), but also short and long term observations of other types of variable X-ray sources. The spacecraft is based on the CubeSat nanosatellite platform with a volume of 16U. The spacecraft carries two types of X-ray telescopes onboard. The first is intended for X-ray transient monitoring and localization, and the second for detailed spectroscopic observation. The X-ray monitor/localization telescope with wide field of view of several arc degrees is used for localization and flux measurement of X-ray transients, as well as for permanent monitoring of Galactic center area. This telescope is based on Lobster Eye X-ray optics together with pixel detector based on the Timepix3 Quad detector. Rapid follow-up observation by soft X-ray spectroscopy is enabled by a second X-ray spectroscopic telescope with limited FOV (Field of View) of several arcmins with no spatial and/or angular resolution. The spectroscopic telescope uses condenser optics based on replicated parabolic total reflection system (or, alternatively, Wolter system) and a Ketek X-ray SDD detector with energy resolution of about 130 eV as a detector. In addition to technical and instrumental aspects, observational strategy and astrophysical issues and justifications are also addressed in the paper.

Analysis of modern observations of meteor showers based on PTM methods

  • Autoři: Sharafutdinova, A.A., Andreev, A.O., Nefedyev, Y.A., prof. RNDr. René Hudec, CSc.,
  • Publikace: Journal of Physics: Conference Series, Volume 2103, International Conference PhysicA.SPb/2021. Bristol: IOP Publishing Ltd., 2021. p. 1-6. Journal of Physics: Conference Series. vol. 2103. ISSN 1742-6588.
  • Rok: 2021
  • DOI: 10.1088/1742-6596/2103/1/012024
  • Odkaz: https://doi.org/10.1088/1742-6596/2103/1/012024
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The work is focused on the analysis of modern observations of meteoroids included in the data bank formed by both professional researchers and amateur astronomers. Based on the modern physical theory of meteoroids (PTM), a new method for analyzing measurements developed, which provides the accuracy comparable with the results of radar observations. Due to the fact that the accuracy of the new method for analyzing meteoroids observations has increased significantly, it became possible to process observations of the Perseid and Leonid showers over a period of 120 years. The use of PTM made it possible for the first time to explain the distribution of meteor echo signals observed at an altitude of 2 MHz, at which the upper part of this distribution refers to an altitude of 140 km. In the process of work, a database of orbital characteristics of meteoroids was created. A method has been developed for modeling the probability of hitting a certain area of a meteor particle with a mass greater than a certain specified value and determining the density of a meteor shower from radio observations as well as a new “tomography” method for calculating the density distribution of sporadic meteors in the sky using radar observations of meteors at the same station with a goniometer. The method allows calculating the density of a meteor shower on the celestial sphere with an angular resolution of 2°. The use of these methods served as a proof that the distribution density of meteoroid showers on the celestial sphere has two planes of symmetry: the first coincides with the plane of the ecliptic, passing through the poles of the Earth, the other one is perpendicular to the plane of the ecliptic.

ESA THESEUS and cataclysmic variables

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The capabilities of the considered space mission THESEUS for investigation of cataclysmic variables (CVs) are discussed

Exploration of the high-redshift universe enabled by THESEUS

  • Autoři: Tanvir, N. R., Le Floc'h, E., Christensen, L., Caruana, J., prof. RNDr. René Hudec, CSc.,
  • Publikace: EXPERIMENTAL ASTRONOMY. 2021, 52(3), 219-244. ISSN 0922-6435.
  • Rok: 2021
  • DOI: 10.1007/s10686-021-09778-w
  • Odkaz: https://doi.org/10.1007/s10686-021-09778-w
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    At peak, long-duration gamma-ray bursts are the most luminous sources of electromagnetic radiation known. Since their progenitors are massive stars, they provide a tracer of star formation and star-forming galaxies over the whole of cosmic history. Their bright power-law afterglows provide ideal backlights for absorption studies of the interstellar and intergalactic medium back to the reionization era. The proposed THESEUS mission is designed to detect large samples of GRBs at z > 6 in the 2030s, at a time when supporting observations with major next generation facilities will be possible, thus enabling a range of transformative science. THESEUS will allow us to explore the faint end of the luminosity function of galaxies and the star formation rate density to high redshifts; constrain the progress of re-ionisation beyond z greater than or similar to 6; study in detail early chemical enrichment from stellar explosions, including signatures of Population III stars; and potentially characterize the dark energy equation of state at the highest redshifts.

Lobster eye type X-ray telescope with chromium-iridium coated tri-layer mirrors

  • Autoři: Ing. Veronika Stieglitz, Ph.D., Döhring, T., Stollenwerk, M., Stadtmüller, J., Maršíková, V., prof. RNDr. René Hudec, CSc., Flachs, D., Burwitz, V., Hartner, G., Rukdee, S., Müller, T., Inneman, A., Schmidt, T., Klementova, M., Zeising, S., Langmeier, A.
  • Publikace: Proc. SPIE 11776, EUV and X-ray Optics, Sources, and Instrumentation. Bellingham WA: The International Society for Optical Engineering (SPIE), 2021. Proceedings of SPIE. vol. 11776. ISSN 0277-786X. ISBN 978-1-5106-4386-4.
  • Rok: 2021
  • DOI: 10.1117/12.2589266
  • Odkaz: https://doi.org/10.1117/12.2589266
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    For space-born astronomical X-ray telescopes, iridium-based reflective layer systems are known as highly effective mirrors coatings. During the recent years, Aschaffenburg University of Applied Sciences and the Czech Technical University in Prague jointly developed stress compensated chromium-iridium coatings for this application. To overcome the disturbing re ectivity reduction of the iridium absorption edge around 2 keV photon energy, thin overcoat layers of chromium were applied in addition. Now a prototype of a wide-field, imaging X-ray telescope of Lobster Eye type is assembled at the company RIGAKU. For this purpose a small series of 34 mirrors based on 100 x 50 mm semiconductor grade silicon substrates has been coated at Aschaffenburg University. The applied tri-layer system consists of a stack of 40 nm chromium, which act as adhesive layer and compensates layer stress, a 30 nm iridium thick reflective layer, and an additional overcoat layer of 6 nm chromium. This layer system have been analysed by AFM and TEM images. The mirrors are assembled into an aluminium frame to build a 2D Lobster Eye type telescope. The designed focal length of this wide field X-ray telescope is two meter. To study the performance of the tri-layer coating system, a twin LE telescope with convenient gold coatings was manufactured also. Performance measurements of both telescopes and under same conditions are planned at the PANTER test facility at the Max-Planck Institute for Extraterrestrial Physics. First experimental results, their comparison with theoretical simulations and the comparison between both models will be presented in this contribution.

Lobster eye X-ray monitors: Recent status

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The capabilities of the considered space mission LOBSTER for investigation of cataclysmic variables (CVs) are discussed

Multi-messenger astrophysics with THESEUS in the 2030s

  • Autoři: Ciolfi, R., Stratta, G., Branchesi, M., Gendre, B., prof. RNDr. René Hudec, CSc.,
  • Publikace: EXPERIMENTAL ASTRONOMY. 2021, 2021(11), 245-275. ISSN 0922-6435.
  • Rok: 2021
  • DOI: 10.1007/s10686-021-09795-9
  • Odkaz: https://doi.org/10.1007/s10686-021-09795-9
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Multi-messenger astrophysics is becoming a major avenue to explore the Universe, with the potential to span a vast range of redshifts. The growing synergies between different probes is opening new frontiers, which promise profound insights into several aspects of fundamental physics and cosmology. In this context, THESEUS will play a central role during the 2030s in detecting and localizing the electromagnetic counterparts of gravitational wave and neutrino sources that the unprecedented sensitivity of next generation detectors will discover at much higher rates than the present. Here, we review the most important target signals from multi-messenger sources that THESEUS will be able to detect and characterize, discussing detection rate expectations and scientific impact.

Stochastic analysis of dynamic processes in the solar activity

  • Autoři: Kostina, E.Y., Khusaenova, E.V., Andreev, A.O., prof. RNDr. René Hudec, CSc., Nefedyev, Y.A.
  • Publikace: Journal of Physics: Conference Series, Volume 2103, International Conference PhysicA.SPb/2021. Bristol: IOP Publishing Ltd., 2021. p. 1-6. Journal of Physics: Conference Series. vol. 2103. ISSN 1742-6588.
  • Rok: 2021
  • DOI: 10.1088/1742-6596/2103/1/012018
  • Odkaz: https://doi.org/10.1088/1742-6596/2103/1/012018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Natural processes existing in complex objects of inanimate and living matter are of a stochastic and non-equilibrium nature. The main problem in the study of such systems is to determine the value of entropy as a quantitative measure of the uncertainty and systematicity of states of dynamical systems in different phase spaces. This paper presents a new method for analyzing active processes of solar dynamics using the theory of non-Markov random discrete processes (NMRDP). The NMRDP theory is based on the Zwanzig-Mori kinetic equations in a finite-difference discrete interpretation. This is consistent with the concept of non-equilibrium statistical condensed matter physics. Qualitative information about the set of behavioral patterns, relaxation processes, dynamic characteristics and internal properties of solar activity can be obtained using NMRDP modeling by the author's methodological approach developed in this work. This approach is focused on the analysis of spectral frequency memory functions, dynamic orthogonal parameters, phase transformations, relaxation and kinetic processes and self-organization in complex physical systems. In this work, for modeling NMRDP, the author's software package APSASA (automated program for solar activity stochastic analysis) was used, which also allows predicting the trend of solar activity for a limited period of time. Modeling NMRDP associated with active processes occurring on the Sun made it possible to build a mathematical model with whose help it is possible to study the regularities and randomness of stochastic processes, as well as to reveal the patterns arising from the recurrence and periodicity of solar activity.

The 2nd generation of the X-ray Multi-Foil optical system for rocket experiment

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Maršíková, V., Inneman, A., Dániel, V.
  • Publikace: Proc. SPIE 11444, Space Telescopes and Instrumentation 2020: Ultraviolet to Gamma Ray. Bellingham (stát Washington): SPIE, 2021. Proc. of SPIE. vol. 11444. ISSN 1996-756X. ISBN 978-1-5106-3676-7.
  • Rok: 2021
  • DOI: 10.1117/12.2576347
  • Odkaz: https://doi.org/10.1117/12.2576347
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This document presents the preliminary results and discussion of the feasibility study of the 2nd generation of the X-ray Multi-Foil Optical (MFO) system for rocket experiment, namely an advanced Lobster Eye (LE) wide field X-ray telescope based on Multi-Foil Optics and designed for use in rocket flights.

The golden age of cataclysmic variables and related objects V concluding remarks IV

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: 5th Golden Age of Cataclysmic Variables and Related Objects. Trieste: Proceedings of Science, 2021. ISSN 1824-8039.
  • Rok: 2021
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The cataclysmic variables continue to represent important part of modern astrophysics, as demonstrated, already fifth time, by the conference Golden Age of Cataclysmic Variables and Related Objects V held on Mondello (Palermo) in September 2019

Time domain astronomy with the THESEUS satellite

  • Autoři: Mereghetti, S., Balman, S., Caballero-Garcia, M., Del Santo, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: EXPERIMENTAL ASTRONOMY. 2021, 2021(11), 309-406. ISSN 0922-6435.
  • Rok: 2021
  • DOI: 10.1007/s10686-021-09809-6
  • Odkaz: https://doi.org/10.1007/s10686-021-09809-6
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    THESEUS is a medium size space mission of the European Space Agency, currently under evaluation for a possible launch in 2032. Its main objectives are to investigate the early Universe through the observation of gamma-ray bursts and to study the gravitational waves electromagnetic counterparts and neutrino events. On the other hand, its instruments, which include a wide field of view X-ray (0.3-5 keV) telescope based on lobster-eye focussing optics and a gamma-ray spectrometer with imaging capabilities in the 2-150 keV range, are also ideal for carrying out unprecedented studies in time domain astrophysics. In addition, the presence onboard of a 70 cm near infrared telescope will allow simultaneous multiwavelegth studies. Here we present the THESEUS capabilities for studying the time variability of different classes of sources in parallel to, and without affecting, the gamma-ray bursts hunt.

What can photographic plate archives contribute to modern astrophysics?

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Applied and Computational Historical Astronomy. Hamburg: Tredition GmBH, 2021. p. 214-238. Beiträge zur Geschichte der Naturwissenschaften. vol. 55. ISBN 978-3-347-27104-3.
  • Rok: 2021
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The potential of world's astronomical photographics archives for modern astronomy and astrophysics is presented and discussed. It is obvious that astronomical photographics data archives still represent valuable data source for astrophysics, and in addition to that, provide valuable historical and cultural heritage. I also discuss the recent status of astronomical photographics archives worldwide with emphasis on digitization efforts.

X-ray testing of the multifoil optical system REX II for rocket experiment

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Maršíková, V., Inneman, A., Dániel, V.
  • Publikace: Proc. SPIE 11776, EUV and X-ray Optics, Sources, and Instrumentation. Bellingham WA: The International Society for Optical Engineering (SPIE), 2021. Proceedings of SPIE. vol. 11776. ISSN 0277-786X. ISBN 978-1-5106-4386-4.
  • Rok: 2021
  • DOI: 10.1117/12.2593763
  • Odkaz: https://doi.org/10.1117/12.2593763
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper presents the 2nd generation of the optical system for Rocket Experiment (REX2). This optical device is based on successful mission REX1. The purpose of REX2 is to verify X-ray optical system consisting of wide- field 2D X-ray Lobster-Eye (LE) optics with an uncooled Quad Timepix3 detector (512x512 px @ 55 um and spectrometer (active area 7 mm2, 145 eV @ 5.9 keV ). The 2D X-ray Lobster-Eye (LE) optics is a combination of two one-dimension LE modules with a focal length of up to 1 m and a FOV better than 4.0 x 4.0 deg. The proposed optical system has imaging capabilities (2.5 to 30 keV) and spectroscopy capabilities (0.2 to 10 keV). The optical system was recently tested in the X-ray vacuum chamber. The preliminary test results are presented and discussed in this paper.

ESA THESEUS and Czech participation

  • DOI: 10.1002/asna.202013787
  • Odkaz: https://doi.org/10.1002/asna.202013787
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent status of the European Space Agency's (ESA) THESEUS (Transient High-Energy Sources and Early Universe Surveyor) project and the recent and expected Czech participation in this project are briefly presented and discussed. THESEUS is a mission concept proposed in response to the ESA's call for medium-size mission (M5) within the Cosmic Vision Programme and selected by ESA on May 7, 2018, to enter an assessment phase A/0 study. The expected Czech participation is on the Soft X-ray Imager (SXI) and a set of four lobster-eye (LE) telescopes, covering a total field of view (FOV) of 1 sr with source location accuracy better than 1-2 arcmin and energy coverage 0.3-6 keV. We also show the prospects of detecting and observing cataclysmic variables (CVs) with the hard X-ray imaging spectrometer (XGIS) and SXI. Since the X-ray spectrum largely determines what emission components and mechanisms can be observed, a combination of these instruments will be very useful. Also if we concentrate on the long-term activity of CVs, it will even be meaningful to use the observations of CVs located in the wide FOVs of XGIS and SXI when searching for and observing other types of events such as gamma-ray bursts.

European Space Agency SMILE and Czech participation

  • DOI: 10.1002/asna.202013785
  • Odkaz: https://doi.org/10.1002/asna.202013785
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) is a space mission which aims to measure Earth's global system responses to solar wind and geomagnetic variations with innovative instrumentation, for example, wide-field X-ray telescope of Lobster-Eye type, on board. It is a collaborative project of the European Space Agency and the Chinese Academy of Sciences. The SMILE international consortium involves the Czech Technical University in Prague and the Czech teams are expected to contribute to the project, mainly to the science and software related to the X-ray telescope. The aim of this short paper is to provide an outline of SMILE and in particular of the Czech participation to this mission, with emphasis on observation of celestial X-ray sources as SMILE secondary science.

Full orbital solution for the binary system in the northern Galactic disc microlensing event Gaia16aye

  • Autoři: Wyrzykowski, L., Mroz, P., Rybicki, K., Gromadzki, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomy & Astrophysics. 2020, 633 ISSN 0004-6361.
  • Rok: 2020
  • DOI: 10.1051/0004-6361/201935097
  • Odkaz: https://doi.org/10.1051/0004-6361/201935097
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I = 12 mag, and it was covered in great detail with almost 25 000 data points gathered by a network of telescopes. We present the photometric and spectroscopic follow-up covering 500 days of the event evolution. We employed a full Keplerian binary orbit microlensing model combined with the motion of Earth and Gaia around the Sun to reproduce the complex light curve. The photometric data allowed us to solve the microlensing event entirely and to derive the complete and unique set of orbital parameters of the binary lensing system. We also report on the detection of the first-ever microlensing space-parallax between the Earth and Gaia located at L2. The properties of the binary system were derived from microlensing parameters, and we found that the system is composed of two main-sequence stars with masses 0.57 +/- 0.05 M-circle dot and 0.36 +/- 0.03 M-circle dot at 780 pc, with an orbital period of 2.88 years and an eccentricity of 0.30. We also predict the astrometric microlensing signal for this binary lens as it will be seen by Gaia as well as the radial velocity curve for the binary system. Events such as Gaia16aye indicate the potential for the microlensing method of probing the mass function of dark objects, including black holes, in directions other than that of the Galactic bulge. This case also emphasises the importance of long-term time-domain coordinated observations that can be made with a network of heterogeneous telescopes.

Note on magnitude estimation on digitized astronomical photographic plates

  • Autoři: prof. RNDr. René Hudec, CSc., Splittgerber, E.
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2020, 50(3), 704-710. ISSN 1335-1842.
  • Rok: 2020
  • DOI: 10.31577/caosp.2020.50.3.704
  • Odkaz: https://doi.org/10.31577/caosp.2020.50.3.704
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The scanned astronomical archival plates offer the possibility of alternative analyses on these data. Apart from a complete evaluation by sophisticated computer programs, the recent efforts offer an alternative fast method of eye estimation method using scanned plates exhibited on computer screens. This alternative method has been investigated by analyzing the light curve of XX Cep on several hundred scanned sky patrol plates from the Sonneberg Observatory plate archive.

Spitzer Observations of the Predicted Eddington Flare from Blazar OJ 287

  • Autoři: Laine, S., Dey, L., Valtonen, M., Gopakumar, A., prof. RNDr. René Hudec, CSc.,
  • Publikace: The Astrophysical Journal Letters. 2020, 894(1), ISSN 2041-8205.
  • Rok: 2020
  • DOI: 10.3847/2041-8213/ab79a4
  • Odkaz: https://doi.org/10.3847/2041-8213/ab79a4
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Binary black hole (BH) central engine description for the unique blazar OJ 287 predicted that the next secondary BH impact-induced bremsstrahlung flare should peak on 2019 July 31. This prediction was based on detailed general relativistic modeling of the secondary BH trajectory around the primary BH and its accretion disk. The expected flare was termed the Eddington flare to commemorate the centennial celebrations of now-famous solar eclipse observations to test general relativity by Sir Arthur Eddington. We analyze the multi-epoch Spitzer observations of the expected flare between 2019 July 31 and 2019 September 6, as well as baseline observations during 2019 February-March. Observed Spitzer flux density variations during the predicted outburst time display a strong similarity with the observed optical pericenter flare from OJ 287 during 2007 September. The predicted flare appears comparable to the 2007 flare after subtracting the expected higher base-level Spitzer flux densities at 3.55 and 4.49 mu m compared to the optical R-band. Comparing the 2019 and 2007 outburst lightcurves and the previously calculated predictions, we find that the Eddington flare arrived within 4 hr of the predicted time. Our Spitzer observations are well consistent with the presence of a nano-Hertz gravitational-wave emitting spinning massive binary BH that inspirals along a general relativistic eccentric orbit in OJ 287. These multi-epoch Spitzer observations provide a parametric constraint on the celebrated BH no-hair theorem.

The development of a selenocentric satellite simulation navigation system by means of the lunar surface model

  • Autoři: Andreev, A., Demina, N., prof. RNDr. René Hudec, CSc., Nefediev, L.
  • Publikace: 20th International Multidisciplinary Scientific Geoconference SGEM 2020. Sofia: International Multidisciplinary Scientific GeoConference SGEM, 2020. p. 739-744. ISSN 1314-2704. ISBN 978-619-7603-04-0.
  • Rok: 2020
  • DOI: 10.5593/sgem2020/6.1/s28.096
  • Odkaz: https://doi.org/10.5593/sgem2020/6.1/s28.096
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This work focuses on the creation of a selenocentric satellite simulation navigation system (SSSNS) using a set of reference objects on the lunar surface. The latter is based on the data from the modern space missions "LRO", "Clementine", "GRAIL"(all - NASA, USA), "SELENE"(JAXA, Japan), and "SMART-1"(European Space Agency). The SSSNS was created to transform measurements taken from in-orbit satellite into the selenocentric inertial reference system. The measurements should be taken by on-board altimeter and laser interferometer. The reliability assessment of the data produced is performed by the methods of regression simulation

The fractal parameters of venusian physical surfaces

  • Autoři: Nefedyev, Y., Andreev, A., Akhmedshina, E., Nefediev, L., prof. RNDr. René Hudec, CSc.,
  • Publikace: 20th International Multidisciplinary Scientific Geoconference SGEM 2020. Sofia: International Multidisciplinary Scientific GeoConference SGEM, 2020. p. 597-603. ISSN 1314-2704. ISBN 978-619-7603-04-0.
  • Rok: 2020
  • DOI: 10.5593/sgem2020/2.1/s08.077
  • Odkaz: https://doi.org/10.5593/sgem2020/2.1/s08.077
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This work focused on study fractal structures on Venus is performed on the basis of observations taken by the “Magellan” spacecraft (NASA). The equipment of this artificial satellite allowed scanning almost the entire surface of Venus using a radar with synthesized aperture of S-band (12 cm) and a microwave radiometer as well as investigating topography by the special radar - altimeter. The uncertainties in some data produced by “Magellan” were filled by the information that had been collected before - in “Venera 15”, “Venera 16”, and “Pioneer” missions. It is worth noting that the choice of basic level surface on Venus is defined by a certain value of potential or a point on its surface through which the geoid passes.

The study of models of space selenophysics using multi-parameter analysis and fractal geometry

  • Autoři: Churkin, K.O., Andreev, A.O., Nefedyev, Y.A., Nefediev, L.A., prof. RNDr. René Hudec, CSc.,
  • Publikace: International Conference PhysicA.SPb/2020. Bristol: Journal of Physics: Conference Series (JPCS), 2020. ISSN 1742-6588.
  • Rok: 2020
  • DOI: 10.1088/1742-6596/1697/1/012024
  • Odkaz: https://doi.org/10.1088/1742-6596/1697/1/012024
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In this work, using multi-parameter harmonic analysis and expansion of altimetry into spherical functions, models of the Moon's physical surface (digital lunar selenocentric map - DLSM) are built, and a comparison of similarity of chosen local areas of the complex lunar structure is performed. The constructed DLSM have radius-vectors of the surface points in accordance with the space measurements taken. As result, the averaged fractal dimension of the selenocentric surfaces profiles models was found to 1.345. The similarity and difference parameters were determined by the author's method using fractal similarity coefficients. The analysis of macrosurfaces based on multi-parameter and fractal methods for the selenocentric models built in this work has not been conducted before.

The use of vector interpretation of projective geometry invariants for analyzing dynamic spatial images

  • Autoři: Nefedyev, Y., Andreev, A., prof. RNDr. René Hudec, CSc., Borovskikh, V.
  • Publikace: 20th International Multidisciplinary Scientific Geoconference SGEM 2020. Sofia: International Multidisciplinary Scientific GeoConference SGEM, 2020. p. 759-766. ISSN 1314-2704. ISBN 978-619-7603-04-0.
  • Rok: 2020
  • DOI: 10.5593/sgem2020/6.1/s28.099
  • Odkaz: https://doi.org/10.5593/sgem2020/6.1/s28.099
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This work focuses on the use of projective geometry methods to determine star positions produced on the basis of positional observations. As is known, projective geometry studies invariant projective transformations. The main feature of projective geometry is the principle of duality, which adds elegant symmetry to many designs. While the properties of the figures that Euclidean geometry deals with are metric, but there are figures that can be converted into one another by movement while maintaining the metric properties, that is, there are more complex properties of geometric figures, it is necessary to use the corresponding methods. The method novelty lies in the fact that the technique allows analyzing images of multiple systems of reference star positions having independent proper motions. The use of this projective geometry apparatus may have a wide application for the study of multi-parameter dynamic coordinate systems and the construction of the considered clusters' models.

Accretion Disk Parameters Determined from the Great 2015 Flare of OJ 287

  • Autoři: Valtonen, M., Zola, S., Pihajoki, P., Enestam, S., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astrophysical Journal. 2019, 882(2), ISSN 0004-637X.
  • Rok: 2019
  • DOI: 10.3847/1538-4357/ab3573
  • Odkaz: https://doi.org/10.3847/1538-4357/ab3573
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In the binary black hole model of OJ. 287, the secondary black hole orbits a much more massive primary, and impacts on the primary accretion disk at predictable times. We update the parameters of the disk, the viscosity, alpha, and the mass accretion rate, <(m)over dot>. We find alpha = 0.26 +/- 0.1 and <(m)over dot> = 0.08 +/- 0.04 in Eddington units. The former value is consistent with Coroniti, and the latter with Marscher & Jorstad. Predictions are made for the 2019 July 30 superflare in OJ. 287. We expect that it will take place simultaneously at the Spitzer infrared channels, as well as in the optical, and that therefore the timing of the flare in optical can be accurately determined from Spitzer observations. We also discuss in detail the light curve of the 2015 flare, and find that the radiating volume has regions where bremsstrahlung dominates, as well as regions that radiate primarily in synchrotron radiation. The former region produces the unpolarized first flare, while the latter region gives rise to a highly polarized second flare.

Astronomical photographic data archives: Recent status

  • DOI: 10.1002/asna.201913676
  • Odkaz: https://doi.org/10.1002/asna.201913676
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    I briefly present and discuss the recent status (with emphasis on digitization and data access) of astronomical photographic data archives worldwide, both photometric and spectroscopic, including various digitization techniques, automated data evaluation pipelines, astrophysical use, and public access. Although there are two major astronomical plate digitization projects (Harvard DASCH USA and APPLAUSE representing German Bamberg, Potsdam and Hamburg plate collections), the majority of astronomical photographic data archives are still awaiting digitization. Numerous plate archives have been visited, and in many of them, the glass plates are affected by various degradation types such as gold decease, sometimes progressing so fast that digitization is of great importance, taking into account the enormous scientific value of these databases.

Effective collecting area of lobster eye optics and optimal value of effective angle

  • Autoři: Tichy, V., Barbera, M., prof. RNDr. René Hudec, CSc., Willingale, R.
  • Publikace: EXPERIMENTAL ASTRONOMY. 2019, 47(1-2), 161-175. ISSN 0922-6435.
  • Rok: 2019
  • DOI: 10.1007/s10686-019-09622-2
  • Odkaz: https://doi.org/10.1007/s10686-019-09622-2
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Effective collecting area represents one of principal parameters of optical systems. The common requirement is to obtain as large effective collecting area as it is possible. The paper presents an analytical method of calculating effective collecting length and its maximization for lobster eye optics. The results are applicable for a Schmidt as well as for an Angel lobster eye geometry used in an astronomical telescope where the source is at infinity such that the incoming rays are parallel. The dependence of effective collecting area vs. geometrical parameters is presented in a form of a simple compact equation. We show that the optimal ratio between mirrors depth and distance (effective angle) does not depend on other geometrical parameters and it is determined only by reflectivity function, i.e. by mirrors (or their coating) material and photon energy. The results can be also used for approximate but fast estimation of performance and for finding the initial point for consequent optimization by ray-tracing simulations.

Isodensity analysis of comets using the collection of digitized Engelhardt Astronomical Observatory photographic plates

  • Autoři: Nefedyev, Y., Andreev, A., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomische Nachrichten. 2019, 340(7), 698-704. ISSN 0004-6337.
  • Rok: 2019
  • DOI: 10.1002/asna.201913677
  • Odkaz: https://doi.org/10.1002/asna.201913677
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The field of astronomy dealing with comets is an important component of modern space investigations. This applies both to the study of physical, chemical, and evolutionary parameters and to the determination of connections between meteor showers and their parental bodies. This paper considers the isodensity analysis of Arend-Roland, 45P/Honda, and Bennett comets using the measurements of photographic plates performed at Engelhardt Astronomical Observatory. On the basis of a software aimed at analyzing the brightness of digital images, structural models for three comets were developed. The isophotes of their nuclei, comas, and tails were determined as well. As the cometary nuclei are the elements of dynamical evolution and processes in the Solar Nebula, the study of a digital database on comets will allow refining the theory of their formation and evolution.

Lobster eye optics: Position determination based on 1D optics with simple code mask

  • DOI: 10.1117/12.2528505
  • Odkaz: https://doi.org/10.1117/12.2528505
  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    Lobster eye X-ray optics in the one dimensional (1D) arrangement has advantages in higher reflectivity, especially for higher energies, compared to classical two dimensional (2D) Schmidt’s arrangement. One dimensional optics can determine only one direction of the incoming beam. There is placed a strip in front of the optics for determining of the second direction. This strip is made of X-ray proof material which blocks the incoming beam and thus causes a gap in the line. Based on these facts, it is possible to determine the position of each point source which has enough signal to gap ratio. Unfortunately, the intensity of sources is not possible to assess by this method.

Multifoil optics for rocket experiments

  • DOI: 10.1117/12.2525541
  • Odkaz: https://doi.org/10.1117/12.2525541
  • Pracoviště: Katedra radioelektroniky, Multirobotické systémy
  • Anotace:
    A novel design of x-ray optical system wide field telescope for astrophysical rocket experiments is investigated and tested in real space flight experiment. The proposed system is based on 1D and 2D modules with Schmidt Lobster Eye (LE) configuration allowing usage of multi-foil mirrors arranged to Schmidt profile.

REX le X-ray telescope experiment overview

  • DOI: 10.1117/12.2527288
  • Odkaz: https://doi.org/10.1117/12.2527288
  • Pracoviště: Katedra radioelektroniky, Multirobotické systémy
  • Anotace:
    The paper summarizes the Rocket EXperiment (REX) Lobster Eye (LE) X-ray Telescope payload results. The experiment was performed by the PennState University with X-ray spectroscope on board a Water Recovery X-Ray Rocket (WRXR) launched on 4th April, 2018. The secondary payload was the REX LE X-ray Telescope. The REX LE X-ray telescope consists of two X-ray telescopes with one-dimensional (1D) and two-dimensional (2D) optics, a visible-light camera and an IR grid-eye. The primary structure consists of a metal housing for the optics and a carbon fiber baffle with the Timepix sensors mounted at the end. The observation data from the experiment are briefly presented and discussed.

Small Binocular Telescope: The new epoch of Burst Alert Robotic Telescope

  • Autoři: Strobl, J., Jelinek, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomische Nachrichten. 2019, 340(7), 633-637. ISSN 0004-6337.
  • Rok: 2019
  • DOI: 10.1002/asna.201913668
  • Odkaz: https://doi.org/10.1002/asna.201913668
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Burst Alert Robotic Telescope (BART) is an autonomous robotic observatory located at the Ondrejov observatory in the Czech Republic. It was constructed in 1996 in order to follow up satellite triggers in hope to provide early observations of Gamma-Ray Burst optical afterglows. We present the new telescope of the observatory "Small Binocular Telescope" (SBT), which has recently obtained its first light and is being prepared for routine observations. The updated system now counts with a dual 0.2-m wide-field optical telescope capable of continuous coverage of an error box of size up to 3.56 x 3.56 degrees.

The Unique Blazar OJ 287 and Its Massive Binary Black Hole Central Engine

  • Autoři: Dey, L., Gopakumar, A., Valtonen, M., Zola, S., prof. RNDr. René Hudec, CSc.,
  • Publikace: Universe. 2019, 5(5), ISSN 2218-1997.
  • Rok: 2019
  • DOI: 10.3390/universe5050108
  • Odkaz: https://doi.org/10.3390/universe5050108
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The bright blazar OJ 287 is the best-known candidate for hosting a nanohertz gravitational wave (GW) emitting supermassive binary black hole (SMBBH) in the present observable universe. The binary black hole (BBH) central engine model, proposed by Lehto and Valtonen in 1996, was influenced by the two distinct periodicities inferred from the optical light curve of OJ 287. The current improved model employs an accurate general relativistic description to track the trajectory of the secondary black hole (BH) which is crucial to predict the inherent impact flares of OJ 287. The successful observations of three predicted impact flares open up the possibility of using this BBH system to test general relativity in a hitherto unexplored strong field regime. Additionally, we briefly describe an ongoing effort to interpret observations of OJ 287 in a Bayesian framework.

Timepix: Influence of temperature and vacuum on equalisation of X-ray detector and its verification

  • DOI: 10.1117/12.2528503
  • Odkaz: https://doi.org/10.1117/12.2528503
  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    The thermal dependence of the semiconductor detector is one of the critical properties. This manuscript describes changes in the threshold scans, equalisation and its verification for the particle counting pixel detector Timepix. The Timepix detector family has great potential for use not only in space, i.e. for small satellite (CubeSat) missions, but also in many other areas like medicine, material testing or particle colliders (i.e. Large Hadron Collider). In this case, several experiments were performed with the Timepix detector under the vacuum conditions as well as ambient conditions with the thermal stabilisation at several temperatures in a range from -15 ◦C to +80 ◦C. This paper describes the early experimental results of the chip temperature dependence. The detector equalisation and validity of the original equalisation dependently on different temperatures is examined. The changes in the detector could cause the errors and shifts of the detection limit for low-energies.

X-ray multi-foil optical system for CubeSat demonstrator

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Marsikova, V., Inneman, A., Havlíková, R.
  • Publikace: EUV and X-ray Optics: Synergy between Laboratory and Space VI. Bellingham: SPIE, 2019. ISSN 0277-786X. ISBN 9781510627307.
  • Rok: 2019
  • DOI: 10.1117/12.2543412
  • Odkaz: https://doi.org/10.1117/12.2543412
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent progress in cube satellites platforms and related miniaturization allows scientific payloads to be considered for these mini satellites. In this paper, we present and discuss some possibilities for miniature astrophysical experiments onboard cube satellites with X-ray and UV optics. Albeit miniature, these payloads are capable to provide valuable scientific results at a low cost. Additional to technical and scientific aspects, there are also educational issues.

X/EUV and UV optics for miniature cubesats payloads

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: EUV and X-ray Optics: Synergy between Laboratory and Space VI. Bellingham: SPIE, 2019. ISSN 0277-786X. ISBN 9781510627307.
  • Rok: 2019
  • DOI: 10.1117/12.2525542
  • Odkaz: https://doi.org/10.1117/12.2525542
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent progress in cube satellites platforms and related miniaturization allows scientific payloads to be considered for these mini satellites. In this paper, we present and discuss some possibilities for miniature astrophysical experiments onboard cube satellites with X-ray and UV optics. Albeit miniature, these payloads are capable to provide valuable scientific results at a low cost. Additional to technical and scientific aspects, there are also educational issues.

AHEAD joint research activity on x-ray optics

  • Autoři: Burwitz, V., Willingale, R., Pareschi, G., prof. RNDr. René Hudec, CSc.,
  • Publikace: Space Telescopes and Instrumentation 2018: Ultraviolet to Gamma Ray. Baltimore: SPIE, 2018. Proceedings of the SPIE. vol. 10699. ISSN 0277-786X. ISBN 9781510619517.
  • Rok: 2018
  • DOI: 10.1117/12.2314109
  • Odkaz: https://doi.org/10.1117/12.2314109
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The progress of X-ray Optics joint research activity of the European Union Horizon 2020 AHEAD project is presented here covering the X-ray optic technologies that are currently being worked on in Europe. These are the Kirkpatrick Baez, lobster eye micropore (SVOM, SMILE), slumped glass, and silicon pore (ATHENA, ARCUS) optics technologies. In this activity detailed comparisons of the measurements, of the different optics produced by the participating optics groups, obtained mainly at the MPEs PANTER X-ray test facility, are compared with simulations. In preparation for the ATHENA mission a study has been made to design the BEaTRiX X-ray test facility for testing individual silicon pore optics mirror modules, and the realization of the facility is now on going. A zone plate collimating optics developed for PANTER is being studied, optimized, and tested at PANTER. This zone plate will be used for characterising a high quality optics module in a parallel beam to verify the BEaTriX performance. Several of the measurements and selected results are presented here.

Astrophysics with digitized astronomical plate archives

  • DOI: 10.1002/asna.201813515
  • Odkaz: https://doi.org/10.1002/asna.201813515
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss the recent status of astrophysical analyses with digitized astronomical plate archives with emphasis on high-energy and transient astrophysics. These data represent huge scientific, historical, and cultural value, but only the recent digitization has enabled their effective use in astrophysics.

Authenticating the Presence of a Relativistic Massive Black Hole Binary in OJ 287 Using Its General Relativity Centenary Flare: Improved Orbital Parameters

  • Autoři: Dey, L., Valtonen, J., Gopakumar, A., Zola, S., prof. RNDr. René Hudec, CSc., Jelinek, M., Štrobl, J.
  • Publikace: Astrophysical Journal. 2018, 866(1), ISSN 0004-637X.
  • Rok: 2018
  • DOI: 10.3847/1538-4357/aadd95
  • Odkaz: https://doi.org/10.3847/1538-4357/aadd95
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations associated with the binary black hole (BBH) central engine of blazar OJ 287 demand the inclusion of gravitational radiation reaction effects beyond the quadrupolar order. It turns out that even the effects of certain hereditary contributions to GW emission are required to predict impact flare timings of OJ 287. We develop an approach that incorporates this effect into the BBH model for OJ 287. This allows us to demonstrate an excellent agreement between the observed impact flare timings and those predicted from ten orbital cycles of the BBH central engine model. The deduced rate of orbital period decay is nine orders of magnitude higher than the observed rate in PSR 1913+16, demonstrating again the relativistic nature of OJ 287's central engine. Finally, we argue that precise timing of the predicted 2019 impact flare should allow a test of the celebrated black hole "no-hair theorem" at the 10% level.

AXRO introduction and historical background

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2018, 48(3), 396-404. ISSN 1335-1842.
  • Rok: 2018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    With the AXRO conference held in December 2017 in Prague, we celebrated the 10th anniversary of these international workshops on astronomical X ray optics. In this contribution a short overview on the AXRO history and its background is given, including a short history of grazing incidence X-ray optics in the Czech republic.

Constraining the period of the ringed secondary companion to the young star J1407 with photographic plates

  • Autoři: Mentel, R., Kenworthy, M., Cameron, D., Scott, E., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomy & Astrophysics. 2018, 619 ISSN 1432-0746.
  • Rok: 2018
  • DOI: 10.1051/0004-6361/201834004
  • Odkaz: https://doi.org/10.1051/0004-6361/201834004
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Context. The 16 Myr old star 1SWASP J140747.93-394542.6 (V1400 Cen) underwent a series of complex eclipses in May 2007, interpreted as the transit of a giant Hill sphere filling debris ring system around a secondary companion, J1407b. No other eclipses have since been detected, although other measurements have constrained but not uniquely determined the orbital period of J1407b. Finding another eclipse towards J1407 will help determine the orbital period of the system, the geometry of the proposed ring system and enable planning of further observations to characterize the material within these putative rings.

Digitization and astrophysical use of Hewitt Camera Archive

  • Autoři: prof. RNDr. René Hudec, CSc., Hudec, L., Howarth, J.
  • Publikace: Astronomische Nachrichten. 2018, 339(5), 412-415. ISSN 0004-6337.
  • Rok: 2018
  • DOI: 10.1002/asna.201813516
  • Odkaz: https://doi.org/10.1002/asna.201813516
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We briefly present the status of digitization and astrophysical use of the Hewitt Camera Archive, UK. These wide-field images, so far little used for astrophysical work, cover both northern as well as southern sky down to limiting mag 13. We also discuss the potential of photographic images taken by satellite tracking cameras for recent astrophysics in general.

Effects of manufacturing inaccuracies on spatial resolution of lobster eye optics

  • Autoři: Tichy, V., Barbera, M., Butcher, G., Lo Cicero, U., prof. RNDr. René Hudec, CSc., Inneman, A.
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2018, 48(3), 405-415. ISSN 1335-1842.
  • Rok: 2018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The performance of Schmidt lobster eye systems are affected by manufacturing inaccuracies in the assembly of individual mirrors or in their non ideal flatness. Such inaccuracies may significantly affect the optics performance and in particular the angular resolution. For this reason we have investigated, via ray -tracing simulations, the effects of such manufacturing inaccuracies. We report the preliminary results of this analysis and compare them with X-ray measurements performed on a test Schmidt lobster eye specimen using the 35 m long X-ray beam -line of the XACT facility of INAF-OAPA in Palermo, Italy.

ESA satellites SMILE and THESEUS

  • Autoři: prof. RNDr. René Hudec, CSc., Branduardi-Raymont, G., Sembay, S., Amati, L.
  • Publikace: Frontier Research in Astrophysics – III (FRAPWS2018). Trieste: SISSA/ISAS, 2018. Proceedings of Science (PoS). vol. 331. ISSN 1824-8039.
  • Rok: 2018
  • DOI: 10.22323/1.331.0086
  • Odkaz: https://doi.org/10.22323/1.331.0086
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    SMILE is a space mission which aims to measure Earth’s global system responses to solar wind and geomagnetic variations with innovative instrumentation, e.g. wide–field X-ray telescope of Lobster–Eye type, on board. It is a collaborative project of the European Space Agency and the Chinese Academy of Sciences. Transient High-Energy Sky and Early Universe Surveyor (THESEUS) is a space mission proposal accepted by the European Space Agency for a phase A study that would study gamma-ray bursts and X–rays for investigating the early universe and for the multi–messenger astrophysics. It involves a Lobster–Eye X–ray telescope as well. The SMILE and THESEUS international consortia involve the Czech Technical University in Prague and the Czech teams are expected to contribute to the projects, mainly to the X–ray telescopes and related science and software.

Image processing of historical astronomical plates

  • Autoři: Skala, P., prof. RNDr. René Hudec, CSc.,
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2018, 48(3), 416-420. ISSN 1335-1842.
  • Rok: 2018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Many fields of X—ray astrophysics require multifrequency data including optical. Long-term data, such as provided by data archives, have special value. Historical astronomical plates were main source of data for more than century, not only for photometry, but also for spectroscopy. There are still millions of plates worldwide which have never been processed by modern computers. There are some standard ways how to process images applicable on astronomic plates. But also many specific methods that must be developed for processing of plates.

JEUMICO and TRILAMICO: Dimensions of successful Bavarian-Czech cooperation

  • Autoři: Doehring, T., prof. RNDr. René Hudec, CSc.,
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2018, 48(3), 430-436. ISSN 1335-1842.
  • Rok: 2018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In December 2017 the two projects JEUMICO (an acronym for Joint European Mirror Cooperation) and TRILAMICO (standing for Trilateral Mirror Collaboration) are ending. Different aspects of this Bavarian -Czech collaboration between Aschaffenburg University and the Czech Technical University in Prague are discussed. The multiple dimensions of this cooperation are scientific achievements, public relation measures, internationalization of education, financial aspects, inter -cultural communication, and also the actual political situation within Europe.

Kirkpatrick Baez X-ray optics for astrophysics: Recent status

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    X-ray optics in Kirkpatrick Baez arrangement represent promising alternative to Wolter optics in common use. We present briefly recent status of design, developments, and tests of this kind of X–ray optics including Kirkpatrick Baez module developed and tested within the EU AHEAD project.

Lobster Eye X-ray optics for astrophysics: Recent status

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    X-ray optics in Lobster Eye arrangement represent promising complementary device to narrow field X-ray optics in common use. We present briefly recent status of design, developments, and tests of X-ray optics including Lobster Eye modules developed and tested within recent space project.

Low-dispersion spectroscopy with cubesats and photographic plates

  • DOI: 10.1002/asna.201813517
  • Odkaz: https://doi.org/10.1002/asna.201813517
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We will briefly present the proposal for the UV experiment based on low-dispersion spectroscopy (LDS) of stars for cubesat mission, as well as the potential of LDS with digitized photographic plates taken mostly by Schmidt telescopes. Extended databases of these records are available at numerous observatories, mainly in the United States, with the total estimated number exceeding 100,000. They represent a valuable source of astrophysical information, especially for automated searches for objects with peculiar spectra as well as for (prominent) spectral changes.

Micro-Nano-Pico-satellites: Complementary tools for big astrophysics

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Frontier Research in Astrophysics – III (FRAPWS2018). Trieste: SISSA/ISAS, 2018. Proceedings of Science (PoS). vol. 331. ISSN 1824-8039.
  • Rok: 2018
  • DOI: 10.22323/1.331.0077
  • Odkaz: https://doi.org/10.22323/1.331.0077
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The picosatellites, recently in development at many institutes and universities worldwide (e.g. Schmidt et al. 2009 and Schilling 2006), represent, apart from growing commercial applications, a challenge for space astronomy and astrophysics, as they can act as complementary tools for modern space astrophysics

Multi-Foil X-ray optics tests at PANTER: Preliminary results

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss preliminary test results performed with selected modules of Multi-Foil X-ray Optics in the MPE PANTER X{ray test facility. Three X-ray optics Multi{Foil modules were tested, namely 1D Kirkpatrick-Baez module, 2D Kirkpatrick-Baez module, both developed within the EU Horizon 2020 AHEAD Project, as well as the Lobster{Eye module REX for the rocket flight experiment.

Progress in digitization of astronomical plate archives

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Frontier Research in Astrophysics – III (FRAPWS2018). Trieste: SISSA/ISAS, 2018. Proceedings of Science (PoS). vol. 331. ISSN 1824-8039.
  • Rok: 2018
  • DOI: 10.22323/1.331.0087
  • Odkaz: https://doi.org/10.22323/1.331.0087
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on the progress in digitization of astronomical plate archives and tests of the scanning devices for digitization of archival astronomical plates. These archives represent large database of stellar, solar, and planetary astronomical data, astrometric, photometric, and spectroscopic, may be useful for numerous applications in modern astrophysics.

Stochastic Modeling of Multiwavelength Variability of the Classical BL Lac Object OJ287 on Timescales Ranging from Decades to Hours

  • Autoři: Goyal, A., Stawarz, L., Zola, S., Marchenko, V., prof. RNDr. René Hudec, CSc., Strobl, J.
  • Publikace: Astrophysical Journal. 2018, 863(2), ISSN 0004-637X.
  • Rok: 2018
  • DOI: 10.3847/1538-4357/aad2de
  • Odkaz: https://doi.org/10.3847/1538-4357/aad2de
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present the results of our power spectral density analysis for the BL Lac object OJ 287, utilizing the Fermi-LAT survey at high-energy.-rays, Swift-XRT in X-rays, several ground-based telescopes and the Kepler satellite in the optical, and radio telescopes at GHz frequencies. The light curves are modeled in terms of continuous-time autoregressive moving average (CARMA) processes. Owing to the inclusion of the Kepler data, we were able to construct for the first time the optical variability power spectrum of a blazar without any gaps across similar to 6 dex in temporal frequencies. Our analysis reveals that the radio power spectra are of a colored-noise type on timescales ranging from tens of years down to months, with no evidence for breaks or other spectral features. The overall optical power spectrum is also consistent with a colored noise on the variability timescales ranging from 117 years down to hours, with no hints of any quasi-periodic oscillations. The X-ray power spectrum resembles the radio and optical power spectra on the analogous timescales ranging from tens of years down to months. Finally, the.-ray power spectrum is noticeably different from the radio, optical, and X-ray power spectra of the source: we have detected a characteristic relaxation timescale in the Fermi-LAT data, corresponding to similar to 150 days, such that on timescales longer than this, the power spectrum is consistent with uncorrelated (white) noise, while on shorter variability timescales there is correlated (colored) noise.

Study of multiple layers coatings for X-ray mirrors

  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    This paper focuses on a theoretical background that motivated the experimental campaign of multiple layer coatings of X-ray mirrors, and the first results of the testing of the prepared samples. Simulations of the use of different overcoats were performed in order to improve the reflectivity of thin iridium coatings designed for X-ray optics effective in the energy up to 10 keV. Samples based on these simulations were prepared and are being tested for the properties that influence the X-ray optical performance, such as layer homogeneity, density and surface micro-roughness. Further the topic of the coating stress was addressed, as it is an issue in case of thin, lightweight X-ray mirrors and affects the time stability of layers. The discussion and preliminary results conclude our contribution.

The THESEUS space mission concept: science case, design and expected performances

  • DOI: 10.1016/j.asr.2018.03.010
  • Odkaz: https://doi.org/10.1016/j.asr.2018.03.010
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    THESEUS is a space mission concept aimed at exploiting Gamma-Ray Bursts for investigating the early Universe and at providing a substantial advancement of multi-messenger and time-domain astrophysics. These goals will be achieved through a unique combination of instruments allowing GRB and X-ray transient detection over a broad field of view (more than 1 sr) with 0.5-1 arcmin localization, an energy band extending from several MeV down to 0.3 keV and high sensitivity to transient sources in the soft X-ray domain, as well as on-board prompt (few minutes) follow-up with a 0.7 m class IR telescope with both imaging and spectroscopic capabilities. THESEUS will be perfectly suited for addressing the main open issues in cosmology such as, e.g., star formation rate and metallicity evolution of the inter-stellar and intra-galactic medium up to redshift similar to 10, signatures of Pop III stars, sources and physics of re-ionization, and the faint end of the galaxy luminosity function. In addition, it will provide unprecedented capability to monitor the X-ray variable sky, thus detecting, localizing, and identifying the electromagnetic counterparts to sources of gravitational radiation, which may be routinely detected in the late '20s/early '30s by next generation facilities like aLIGO/ aVirgo, eLISA, KAGRA, and Einstein Telescope. THESEUS will also provide powerful synergies with the next generation of multi-wavelength observatories (e.g., LSST, ELT, SKA, CTA, ATHENA). (C) 2018 COSPAR. Published by Elsevier Ltd. All rights reserved.

THESEUS: A key space mission concept for Multi-Messenger Astrophysics

  • Autoři: Stratta, G., Ciolfi, R., Amati, L., Bozzo, E., prof. RNDr. René Hudec, CSc., Szecsi, D.
  • Publikace: Advances in Space Research. 2018, 62(3), 662-682. ISSN 0273-1177.
  • Rok: 2018
  • DOI: 10.1016/j.asr.2018.04.013
  • Odkaz: https://doi.org/10.1016/j.asr.2018.04.013
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent discovery of the electromagnetic counterpart of the gravitational wave source GW170817, has demonstrated the huge informative power of multi-messenger observations. During the next decade the nascent field of multi-messenger astronomy will mature significantly. Around 2030 and beyond, third generation ground-based gravitational wave detectors will be roughly ten times more sensitive than the current ones. At the same time, neutrino detectors currently upgrading to multi km(3) telescopes, will include a 10 km(3) facility in the Southern hemisphere. In this review, we describe the most promising sources of high frequency gravitational waves and neutrinos that will be detected in the next two decades. In this context, we show the important role of the Transient High Energy Sky and Early Universe Surveyor (THESEUS), a mission concept accepted by ESA for phase A study and proposed by a large international collaboration in response to the call for the Cosmic Vision Programme M5 missions. THESEUS aims at providing a substantial advancement in early Universe science as well as in multi-messenger and time-domain astrophysics, operating in strong synergy with future gravitational wave and neutrino detectors as well as major ground- and space-based telescopes. This review is an extension of the THESEUS white paper (Amati et al., 2017), also in light of the discovery of GW170817/GRB170817A that was announced on October 16th, 2017. (C) 2018 COSPAR. Published by Elsevier Ltd. All rights reserved.

Application of biomimetics in X-ray optics

  • Autoři: prof. RNDr. René Hudec, CSc., Remisova, K.
  • Publikace: Proc. SPIE 10235, EUV and X-ray Optics: Synergy between Laboratory and Space V. Bellingham WA: The International Society for Optical Engineering (SPIE), 2017. Proceedings of SPIE. vol. 10235. ISSN 0277-786X. ISBN 978-1-5106-0972-3.
  • Rok: 2017
  • DOI: 10.1117/12.2266591
  • Odkaz: https://doi.org/10.1117/12.2266591
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The principles of biomimetics were successfully applied in X ray optics in the past and recently, e.g. in Lobster-Eye optical systems. However, the recent growing knowledge of sea vision, especially of peculiar mirror eyes of scallops, crustaceans, and deep sea fishes, makes it possible to consider other such applications. One of the most important discoveries is finding of mirror eyes in deep sea fish Dolichopteryx longipes based on large large numbers of very small mirror plates organized in specific positions. This arrangement may even include principles of active optics. We report on ongoing study with focus on understanding of very specific mirror eyes of sea animals and how they may help us to design and develop special optics for scientific applications. We study the ways these mirror eyes work, what are the advantages of these peculiar eye arrangements, and whether these optics can be used in advanced devices, e.g. X-ray optics. We will briefly present and discuss the preliminary results.

Astrophysical payloads for picosatellites

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2017, 47(2), 143-150. ISSN 1335-1842.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent progress in cubesatellite technology allows to consider scientific applications of these minsatellites including astrophysical research. Miniature X ray and UV payloads may serve as an example.

Biomimetics and astronomical X-ray optics

  • Autoři: prof. RNDr. René Hudec, CSc., Remisova, K.
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2017, 47(2), 67-75. ISSN 1335-1842.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Some sea and water animals have strange mirror eyes which have (or might have) potential application in science and technology in general and in X-ray astrophysics in particular. While the principles of mirror eyes of decapods (lobsters, crayfishes) are already applied in space and ground-based imaging experiments, the mirror eyes of specific fishes are still very little investigated.

Colors of the universe – market study on optical filters for professional astronomy

  • Autoři: Skala, P., Dohring, T., prof. RNDr. René Hudec, CSc.,
  • Publikace: DGaO-PROCEEDINGS. Erlangen: Deutsche Gesellschaft für angewandte Optik e.V., 2017. ISSN 1614-8436.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Colors of the universe – market study on optical filters for professional astronomy will be presented and discussed

Current developments and tests of small x-ray optical systems for space applications

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Inneman, A., Maršíková, V., Doubravova, D.
  • Publikace: Proc. SPIE 10235, EUV and X-ray Optics: Synergy between Laboratory and Space V. Bellingham WA: The International Society for Optical Engineering (SPIE), 2017. Proceedings of SPIE. vol. 10235. ISSN 0277-786X. ISBN 978-1-5106-0972-3.
  • Rok: 2017
  • DOI: 10.1117/12.2271173
  • Odkaz: https://doi.org/10.1117/12.2271173
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The paper addresses the X-ray monitoring for astrophysical applications. A novel approach based on the use of 1D and 2D "Lobster eye" optics in combination with Timepix X-ray detector in the energy range 3 - 40 keV was further studied. Wide-field optical system of this type has not been used in space yet. Designed wide-field optical system combined with Timepix X-ray detector is described together with latest experimental results obtained during laboratory tests. Proposed project includes theoretical study and a functional sample of the Timepix X-ray detector with multifoil wide-field X-ray "Lobster eye" optics. Using optics to focus X-rays on a detector is the only solution in cases where intensity of impinging X-ray radiation is below the sensitivity of the detector, e.g. while monitoring astrophysical objects in space, or phenomena in the Earth's atmosphere. The optical system is considered to be used in a student rocket experiment.

CVs Astrophysics with LOBSTER and ESA LOFT

Data processing from lobster eye type optics

  • DOI: 10.1117/12.2265724
  • Odkaz: https://doi.org/10.1117/12.2265724
  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    Wolter I optics are commonly used for imaging in X-Ray spectrum. This system uses two reflections, and at higher energies, this system is not so much efficient but has a very good optical resolution. Here is another type of optics Lobster Eye, which is using also two reflections for focusing rays in Schmidt's or Angel's arrangement. Here is also possible to use Lobster eye optics as two one dimensional independent optics. This paper describes advantages of one dimensional and two dimensional Lobster Eye optics in Schmidt's arrangement and its data processing - find out a number of sources in wide field of view. Two dimensional (2D) optics are suitable to detect the number of point X-ray sources and their magnitude, but it is necessary to expose for a long time because a 2D system has much lower transitivity, due to double reflection, compared to one dimensional (1D) optics. Not only for this reason, two 1D optics are better to use for lower magnitudes of sources. In this case, additional image processing is necessary to achieve a 2D image. This article describes of approach an image reconstruction and advantages of two 1D optics without significant losses of transitivity.

Fish eye optics

  • Autoři: prof. RNDr. René Hudec, CSc., Michalova, S.
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2017, 47(2), 94-99. ISSN 1335-1842.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on small student (high school) project of the Czech Academy of Sciences dealing with animal (fish) eyes and possible application in science and technology. Albeit most fishes have refractive eyes, the recent discoveries confirm that some fishes have reflective eyes with strange arrangements as well.

JEUMICO – Bayerisch-tschechische Kooperation zur Entwicklung von Röntgenteleskopen

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    JEUMICO – Bayerisch-tschechische Kooperation zur Entwicklung von Röntgenteleskopen will be presented and discused

JEUMICO: Czech-Bavarian astronomical X-ray optics project

  • Autoři: prof. RNDr. René Hudec, CSc., Doehring, T.
  • Publikace: Contributions of the Astronomical Observatory Skalnaté Pleso. 2017, 47(2), 170-177. ISSN 1335-1842.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Within the project JEUMICO, an acronym for Joint European Mirror Competence, the Aschaffenburg University of Applied Sciences and the Czech Technical University in Prague started a collaboration to develop mirrors for X-ray telescopes. Corresponding mirror segments use substrates of flat silicon wafers which are coated with thin iridium films, as this material is promising high re reflectivity in the X-ray range of interest. The sputtering parameters are optimized in the context of the expected reflectivity of the coated X-ray mirrors. In near future measurements of the assembled mirror modules optical performances are planned at an X-ray test facility.

Lobster Eye Optics and Biomimetics

  • Autoři: prof. RNDr. René Hudec, CSc., Dohring, T., Remisova, K.
  • Publikace: DGaO-PROCEEDINGS. Erlangen: Deutsche Gesellschaft für angewandte Optik e.V., 2017. ISSN 1614-8436.
  • Rok: 2017
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Lobster Eye Optics and Biomimetics - the results obtained in the ongoing collaborative project will be presented

Lobster eye X-ray optics: Data processing from two 1D modules

  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    The X-ray imaging is usually done by Wolter I telescopes. They are suitable for imaging of a small part of the sky, not for all-sky monitoring. This monitoring could be done by a Lobster eye optics which can theoretically have a field of view up to 360deg. All sky monitoring system enables a quick identification of source and its direction. This paper describes the possibility of using two independent one-dimensional Lobster Eye modules for this purpose instead of Wolter I and their post-processing into an 2D image. This arrangement allows scanning with less energy loss compared to Wolter I or two-dimensional Lobster Eye optics. It is most suitable especially for very weak sources.

Perspectives of observing the color indices of optical afterglows of gamma-ray bursts with ESA Gaia

  • DOI: 10.1007/s10686-017-9550-5
  • Odkaz: https://doi.org/10.1007/s10686-017-9550-5
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We propose a strategy for detecting and analyzing optical afterglows (OAs) of long gamma-ray bursts (GRBs) without the need to obtain their light curves. This approach is useful for the Gaia satellite, which provides sampled optical ultra-low-dispersion spectroscopic observations of the sky. For this purpose, we show that most OAs of long GRBs display specific values of some of their color indices, representing synchrotron emission of the jet. They are stable in time during the event. These indices, which can be determined from the spectra, are very similar for the ensemble of OAs with redshift z < 3.5 and display a strong clustering in some color-color diagrams. These indices also enable to constrain the properties of the local interstellar medium of GRBs. The long-lasting mapping of the sky with the Gaia instruments also gives us a hope to search for the so-called orphan afterglows, which, according to some authors, can be considerably more numerous than OAs of the observed GRBs. We also show how to resolve OAs from other transients in the Gaia data. The color indices and the properties of the quiescent sources (host galaxies of OAs detectable later by the large ground-based telescopes at the co-ordinates of the OA determined by Gaia) would tell us which one, among transients detected by Gaia, is a GRB OA.

Photographic Sky Surveys and Cataclysmic Variables: Recent progress

  • DOI: 10.22323/1.255.0041
  • Odkaz: https://doi.org/10.22323/1.255.0041
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on an application of astronomical photographic plate archives in study of cataclysmic variables and related inventory and digitization of archival astronomical plates including metadata. These archives represent huge database of historical astronomical data, astrometric, photometric, and spectroscopic, with in general many applications in modern astrophysics.

Polarization and spectral energy distribution in OJ~287 during the 2016/17 outbursts

  • Autoři: Valtonen, M., Yola, S., Jermak, H., Ciprini, S., prof. RNDr. René Hudec, CSc.,
  • Publikace: Galaxies. 2017, 2017(1), ISSN 2075-4434.
  • Rok: 2017

Study of Cataclysmic Variables with LDS Sky Surveys and ESA Gaia

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The goal of this paper is to discuss the capabilities of ESA satellite missions Gaia and of the photographic LDS surveys for investigation of cataclysmic variables (CVs). We show that both of them can contribute to the study of CVs and related objects. Spectrophotometry and lowdispersion spectroscopy are the most important for CV analyses with the observations of Gaia. We present the possible strategies for investigation of CVs in the sampled photometric and spectroscopic data provided by Gaia. E.g. statistical properties of the long-term activity of various types of CVs can be determined from them.

The Golden Age of Cataclysmic Variables and Related Objects–III: Concluding Remarks

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The cataclysmic variables continue to represent important part of modern astrophysics, as demonstrated, already third time, by the conference Golden Age of Cataclysmic Variables and Related Objects III held on Mondello (Palermo) in September 2015.

VZLUSAT-1: Nanosatellite with miniature lobster eye X-ray telescope and qualification of the radiation shielding composite for space application

  • DOI: 10.1016/j.actaastro.2017.08.004
  • Odkaz: https://doi.org/10.1016/j.actaastro.2017.08.004
  • Pracoviště: Katedra radioelektroniky, Multirobotické systémy
  • Anotace:
    In the upcoming generation of small satellites there is a great potential for testing new sensors, processes and technologies for space and also for the creation of large in situ sensor networks. It plays a significant role in the more detailed examination, modelling and evaluation of the orbital environment. Scientific payloads based on the CubeSat technology are also feasible and the miniature X-ray telescope described in this paper may serve as an example. One of these small satellites from CubeSat family is a Czech CubeSat VZLUSAT-1, which is going to be launched during QB50 mission in 2017. This satellite has dimensions of 100 mm × 100 mm × 230 mm. The VZLUSAT-1 has three main payloads. The tested Radiation Hardened Composites Housing (RHCH) has ambitions to be used as a structural and shielding material to protect electronic devices in space or for constructions of future manned and unmanned spacecraft as well as Moon or Martian habitats. The novel miniaturized X-ray telescope with a Lobster Eye (LE) optics represents an example of CubeSat’s scientific payload. The telescope has a wide field of view and such systems may be essential in detecting the X-ray sources of various physical origin. VZLUSAT-1 also carries the FIPEX payload which measures the molecular and atomic oxygen density among part of the satellite group in QB50 mission. The VZLUSAT-1 is one of the constellation in the QB50 mission that create a measuring network around the Earth and provide multipoint, in-situ measurements of the atmosphere. This paper presents the VZLUSAT-1 satellite including the details about subsystems and payloads. The spacecraft was built between 2011 and 2015. In 2017, our VZLUSAT-1 team has finished the testing phase on a protoflight model and the VZLUSAT-1 is ready to be launched on a circular polar orbit at altitude 500 km ± 20 km.

A Decade of GRB Follow-Up by BOOTES in Spain (2003–2013)

  • Autoři: Jelínek, M., Castro-Tirado, A. J., Cunniffe, R., Gorosabel, J., doc. Ing. Stanislav Vítek, Ph.D., Kubánek, P., de Ugarte Postigo, A., Guziy, S., Tello, J. C., prof. Mgr. Petr Páta, Ph.D., Sánchez-Ramírez, R., Oates, S., Jeong, S,, Štrobl, J., Castillo-Carrión, S., Sanguino, T. M., Rabaza, O., Pérez-Ramírez, D., Fernández-Muñoz, R., de la Morena Carretero, B. A., prof. RNDr. René Hudec, CSc., Reglero, V., Sabau-Graziati, L.
  • Publikace: Advances in Astronomy. 2016, 2016 ISSN 1687-7969.
  • Rok: 2016
  • DOI: 10.1155/2016/1928465
  • Odkaz: https://doi.org/10.1155/2016/1928465
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This article covers ten years of GRB follow-ups by the Spanish BOOTES stations: 71 follow-ups providing 23 detections. Follow-ups by BOOTES-1B from 2005 to 2008 were given in a previous article and are here reviewed and updated, and additional detection data points are included as the former article merely stated their existence. The all-sky cameras CASSANDRA have not yet detected any GRB optical afterglows, but limits are reported where available.

A Search for QPOs in the Blazar OJ287: Preliminary Results from the 2015/2016 Observing Campaign

  • Autoři: Zola, S., Valtonen, M., Bhatta, G., Goyal, A., prof. RNDr. René Hudec, CSc.,
  • Publikace: Galaxies. 2016, 4(4), 1-500. ISSN 2075-4434.
  • Rok: 2016
  • DOI: 10.3390/galaxies4040041
  • Odkaz: https://doi.org/10.3390/galaxies4040041
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We analyse the light curve in the R band of the blazar OJ287, gathered during the 2015/2016 observing season. We did a search for quasi-periodic oscillations (QPOs) using several methods over a wide range of timescales. No statistically significant periods were found in the high-frequency domain both in the ground-based data and in Kepler observations. In the longer-period domain, the Lomb-Scargle periodogram revealed several peaks above the 99% significance level. The longest one-about 95 days-corresponds to the innermost stable circular orbit (ISCO) period of the more massive black hole. The 43-day period could be an alias, or it can be attributed to accretion in the form of a two-armed spiral wave.

Activity from the Be/X-ray binary system V0332+53 during its intermediate-luminosity outburst in 2008

  • Autoři: Caballero-Garcia, M., Camero-Arranz, A., Arabaci, M O, prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomy & Astrophysics. 2016, 589(9), ISSN 1432-0746.
  • Rok: 2016

Astrophysics of "extreme" solar-like stars

  • Autoři: Caballero-García, M.D., Castro-Tirado, A.J., Claret, A., Gazeas, K., RNDr. Vojtěch Šimon, Ph.D., Jelínek, M., Cwiek, A., Zarnecki, A.F., Oates, S., Jeong, S., prof. RNDr. René Hudec, CSc.,
  • Publikace: Revista Mexicana de Astronomia y Astrofisica: Serie de Conferencias. 2016, 48 59-63. ISSN 1405-2059.
  • Rok: 2016
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Only a few red dwarf flaring stars in the solar neighbourhood have undergone exceptional events called superflares. They have been detected with high-energy satellites (Swift) and have been proven to be powerful events (both in intensity and energy) and potentially hazardous for any extraterrestial life. The physics of these events can be understood as an extrapolation of the (much) weaker activity already occurring in the most powerful solar flares occurring in the Sun. Nevertheless, the origin (why?) of these superflares occur is currently unknown. A recent study presents the optical and X-ray long-term evolution of the emission by the super-flare from the red-dwarf star DG CVn undertaken in 2 014. In that paper we comment on the context of these observations and on the properties that can be derived through the analysis of them.

Effective algorithm for ray-tracing simulations of lobster eye and similar reflective optical systems

  • Autoři: Tichý, V., prof. RNDr. René Hudec, CSc., Němcová, Š.
  • Publikace: EXPERIMENTAL ASTRONOMY. 2016, 41(3), 377-392. ISSN 0922-6435.
  • Rok: 2016

eXTP: enhanced X-ray Timing and Polarimetry Mission

  • Autoři: Zhang, S. N., Feroci, M., Santangelo, A., Dong, Y. W., prof. RNDr. René Hudec, CSc.,
  • Publikace: Space Telescopes and Instrumentation 2016. Baltimore: SPIE, 2016. Proceedings of SPIE. vol. 9905. ISSN 0277-786X. ISBN 9781510601895.
  • Rok: 2016
  • DOI: 10.1117/12.2232034
  • Odkaz: https://doi.org/10.1117/12.2232034
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    eXTP is a science mission designed to study the state of matter under extreme conditions of density, gravity and magnetism. Primary goals are the determination of the equation of state of matter at supra-nuclear density, the measurement of QED effects in highly magnetized star, and the study of accretion in the strong-field regime of gravity. Primary targets include isolated and binary neutron stars, strong magnetic field systems like magnetars, and stellar-mass and supermassive black holes. The mission carries a unique and unprecedented suite of state-of-the-art scientific instruments enabling for the first time ever the simultaneous spectral-timing-polarimetry studies of cosmic sources in the energy range from 0.5-30 keV (and beyond). Key elements of the payload are: the Spectroscopic Focusing Array (SFA) - a set of 11 X-ray optics for a total effective area of similar to 0.9 m(2) and 0.6 m(2) at 2 keV and 6 keV respectively, equipped with Silicon Drift Detectors offering < 180 eV spectral resolution; the Large Area Detector (LAD) - a deployable set of 640 Silicon Drift Detectors, for a total effective area of similar to 3.4 m(2), between 6 and 10 keV, and spectral resolution better than 250 eV; the Polarimetry Focusing Array (PFA) - a set of 2 X-ray telescope, for a total effective area of 250 cm(2) at 2 keV, equipped with imaging gas pixel photoelectric polarimeters; the Wide Field Monitor (WFM) - a set of 3 coded mask wide field units, equipped with position-sensitive Silicon Drift Detectors, each covering a 90 degrees x 90 degrees field of view. The eXTP international consortium includes major institutions of the Chinese Academy of Sciences and Universities in China, as well as major institutions in several European countries and the United States. The predecessor of eXTP, the XTP mission concept, has been selected and funded as one of the so-called background missions in the Strategic Priority Space Science Program of the Chinese Academy of Sciences since 201

Frontier Research in Astrophysics 2016 Concluding Remarks

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: 2nd Frontier Research in Astrophysics, FRAPWS2016. Trieste: SISSA/ISAS, 2016. Proceedings of Science. vol. 2016-May. ISSN 1824-8039.
  • Rok: 2016
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper contains the printed version of the concluding remarks I gave at the Mondello Workshop 2016 on Frontier Research in Astrophysics – II, held in Mondello, Italy, May 23–28, 2016.

LOBSTER EYE X-Ray Wide Field Telescopes and Monitors: Recent Progress

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: 2nd Frontier Research in Astrophysics, FRAPWS2016. Trieste: SISSA/ISAS, 2016. Proceedings of Science. vol. 2016-May. ISSN 1824-8039.
  • Rok: 2016
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Wide field X-ray monitors of Lobster Eye (LE) type were demonstrated to play an important role in modern astrophysics. We report on recent progress with emphasis on miniature LE telescopes.

Localization and broadband follow-up of the gravitational-wave transient GW150914

  • DOI: 10.3847/2041-8205/826/1/L13
  • Odkaz: https://doi.org/10.3847/2041-8205/826/1/L13
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams.

New Perspectives in Multispectral Sky Monitoring

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: XI Multifrequency Behaviour of High Energy Cosmic Sources Workshop 25-30 May 2015 Palermo, Italy. Trieste: SISSA/ISAS, 2016. pp. 1-10. PoS. ISSN 1824-8039.
  • Rok: 2016
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    New Perspectives in Multispectral Sky Monitoring are presented and discussed

PRIMARY BLACK HOLE SPIN IN OJ 287 AS DETERMINED BY THE GENERAL RELATIVITY CENTENARY FLARE

  • Autoři: Valtonen, MJ, Zola, S, Ciprini, S, prof. RNDr. René Hudec, CSc.,
  • Publikace: The Astrophysical Journal Letters. 2016, 819(2), ISSN 2041-8205.
  • Rok: 2016

SMILE ESA CAS Satellite Mission

  • Autoři: prof. RNDr. René Hudec, CSc., Branduardi-Raymont, R., Sembay, S.
  • Publikace: 2nd Frontier Research in Astrophysics, FRAPWS2016. Trieste: SISSA/ISAS, 2016. Proceedings of Science. vol. 2016-May. ISSN 1824-8039.
  • Rok: 2016
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    SMILE is a space mission which aims to measure Earth’s global system responses to solar wind and geomagnetic variations with innovative instrumentation, e.g. wide-field X-ray telescope of Lobster-Eye type, on board. It is a collaborative project of the European Space Agency and Chinese Academy of Sciences. The SMILE international consortium involves the Czech Technical University in Prague and the Czech teams are expected to contribute to the project, mainly to the X-ray telescope.

SUPPLEMENT: "LOCALIZATION AND BROADBAND FOLLOW-UP OF THE GRAVITATIONAL-WAVE TRANSIENT GW150914" (2016, ApJL, 826, L13)

  • DOI: 10.3847/0067-0049/225/1/8
  • Odkaz: https://doi.org/10.3847/0067-0049/225/1/8
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This Supplement provides supporting material for Abbott et al. (2016a). We briefly summarize past electromagnetic (EM) follow-up efforts as well as the organization and policy of the current EM follow-up program. We compare the four probability sky maps produced for the gravitational-wave transient GW150914, and provide additional details of the EM follow-up observations that were performed in the different bands.

The LOFT mission concept - A status update

  • Autoři: Feroci, M., Bozzo, E., Brandt, S., Hernanz, M., prof. RNDr. René Hudec, CSc., Petráček, V.
  • Publikace: Proceedings of SPIE. Bellingham (stát Washington): SPIE, 2016. ISSN 0277-786X. ISBN 978-1-5106-0189-5.
  • Rok: 2016
  • DOI: 10.1117/12.2233161
  • Odkaz: https://doi.org/10.1117/12.2233161
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Large Observatory For x-ray Timing (LOFT) is a mission concept which was proposed to ESA as M3 and M4 candidate in the framework of the Cosmic Vision 2015-2025 program. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument and the uniquely large field of view of its wide field monitor, LOFT will be able to study the behaviour of matter in extreme conditions such as the strong gravitational field in the innermost regions close to black holes and neutron stars and the supra-nuclear densities in the interiors of neutron stars. The science payload is based on a Large Area Detector (LAD, > 8m(2) effective area, 2-30 keV, 240 eV spectral resolution, 1 degree collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e. g., GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the current technical and programmatic status of the mission.

Alternative technologies and arrangements for future space x-ray telescopes

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Inneman, A.
  • Publikace: Proc. SPIE 9510, EUV and X-ray Optics: Synergy between Laboratory and Space IV. Prague: SPIE - The International Society for Optical Engineering, 2015. Proceedings of SPIE. vol. 9510. ISSN 0277-786X. ISBN 978-1-62841-631-2.
  • Rok: 2015

Analytical description of lobster eye and similar multi-foil optics

  • Autoři: Tichý, V., prof. RNDr. René Hudec, CSc., Barbera, M.
  • Publikace: Proc. SPIE 9510, EUV and X-ray Optics: Synergy between Laboratory and Space IV. Prague: SPIE - The International Society for Optical Engineering, 2015. Proceedings of SPIE. vol. 9510. ISSN 0277-786X. ISBN 978-1-62841-631-2.
  • Rok: 2015
  • DOI: 10.1117/12.2178678
  • Odkaz: https://doi.org/10.1117/12.2178678
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Analytical equations describing lobster eye optical parameters on dependence on its geometric parameters are presented. The paper partially gives review of main previously known results. At next, the paper gives new results discussing parameters, that were not included to previously published models but may be significant. The results are applicable for a Schmidt as well as for an Angel lobster eye and for some related multi-foil systems.

Applications of lobster eye optics

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Inneman, A., Tichý, V.
  • Publikace: Proc. SPIE 9510, EUV and X-ray Optics: Synergy between Laboratory and Space IV. Prague: SPIE - The International Society for Optical Engineering, 2015. Proceedings of SPIE. vol. 9510. ISSN 0277-786X. ISBN 978-1-62841-631-2.
  • Rok: 2015
  • DOI: 10.1117/12.2177792
  • Odkaz: https://doi.org/10.1117/12.2177792
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Applications of wide field Lobster Eye X ray telescopes are presented and discussed. The wide field X ray optics was originally proposed for use in X-ray astronomy, but there are numerous other application areas as well.

Bamberg Observatory Photographic Plate Archive in the context of European Research, Related Past and Recent Projects and Use in Modern Astrophysics.

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Astronomie in Franken. Hamburg: Universitat Hamburg, 2015. Nuncius Hamburgensis Beiträge zur Geschichte der Naturwissenschaften Band 31. ISSN 1610-6164. ISBN 978-3-7345-0248-4.
  • Rok: 2015
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    I will review and discuss the Bamberg Observatory photographic plate archive in the context of German and European astronomy, its past and recent projects, as well as applications in modern astrophysics. The archive contains almost 40,000 wide field survey photographic glass plates taken mostly at Bamberg or at southern Bamberg observing stations abroad, but there are also several smaller plate series such as the Bamberg Schmidt plate collection (stellar spectra taken with objective prism) or collection of old plates taken in 1911 at the Goettingen Observatory.

Early optical follow-up of the nearby active star DG CVn during its 2014 superflare

  • DOI: 10.1093/mnras/stv1565
  • Odkaz: https://doi.org/10.1093/mnras/stv1565
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    DG Canum Venaticorum (DG CVn) is a binary system in which one of the components is an M-type dwarf ultrafast rotator, only three of which are known in the solar neighbourhood. Observations of DG CVn by the Swift satellite and several ground-based observatories during its superflare event on 2014 allowed us to perform a complete hard X-ray-optical follow-up of a superflare from the red-dwarf star. The observations support the fact that the superflare can be explained by the presence of (a) large active region(s) on the surface of the star. Such activity is similar to the most extreme solar flaring events. This points towards a plausible extrapolation between the behaviour from the most active red-dwarf stars and the processes occurring in the Sun.

GLORIA and Study of Cataclysmic Variables

  • Autoři: prof. RNDr. René Hudec, CSc., RNDr. Vojtěch Šimon, Ph.D.,
  • Publikace: THE GOLDEN AGE OF CATACLYSMIC VARIABLES AND RELATED OBJECTS - II. Praha: České vysoké učení technické v Praze, 2015. pp. 303-307. Acta Polytechnica Proceedings. ISSN 2336-5382. ISBN 978-80-01-05688-2.
  • Rok: 2015
  • DOI: 10.14311/APP.2015.02.0303
  • Odkaz: https://doi.org/10.14311/APP.2015.02.0303
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on the ongoing EU FP7 Project GLORIA (GLObal Robotic-telescopes Intelligent Array) with emphasis on possibility of investigation of cataclysmic variables by users. GLORIA will enable the first free and open-access network of robotic telescopes in the world. We show several examples of the not often used topics (but suitable for GLORIA) for the studies of activity of cataclysmic variables, e.g. search for outbursts in intermediate polars and the fluctuations of brightness in their quiescence, and investigation of the optical counterparts of supersoft X-ray sources.

Golden Era of Cataclysmic Variables and Related Objects II: Concluding Remarks

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: THE GOLDEN AGE OF CATACLYSMIC VARIABLES AND RELATED OBJECTS - II. Praha: České vysoké učení technické v Praze, 2015. pp. 325-327. Acta Polytechnica Proceedings. ISSN 2336-5382. ISBN 978-80-01-05688-2.
  • Rok: 2015
  • DOI: 10.14311/APP.2015.02.0325
  • Odkaz: https://doi.org/10.14311/APP.2015.02.0325
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The cataclysmic variables continue to represent important part of modern astrophysics, as demonstrated, already second time, by the productive and successful conference Golden Era of Cataclysmic Variables and Related Objects II held on Mondello (Palermo) in September 2013

INITIAL FOLLOW-UP OF OPTICAL TRANSIENTS WITH COLORES USING THE BOOTES NETWORK

  • Autoři: Caballero Garcia, M., Jelinek, M., Castro-Tirado, A., prof. RNDr. René Hudec, CSc.,
  • Publikace: Acta Polytechnica. 2015, 55(2), 81-85. ISSN 1805-2363.
  • Rok: 2015
  • DOI: 10.14311/AP.2015.55.0081
  • Odkaz: https://doi.org/10.14311/AP.2015.55.0081
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Burst Observer and Optical Transient Exploring System (BOOTES) is a network of telescopes that allows the continuous monitoring of transient astrophysical sources. It was originally devoted to the study of the optical emission from gamma-ray bursts (GRBs) that occur in the Universe. In this paper we show the initial results obtained using the spectrograph COLORES (mounted on BOOTES-2), when observing optical transients (OTs) of diverse nature.

Lobster-Eye All-Sky Soft X-ray Monitors

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The idea of a satellite providing monitoring of specified sky areas in soft X-rays is presented. Observation plan could include also e.g. searching for X-ray afterglows of gamma-ray bursts. The spacecraft could be of the nano-satellite class. Using of Schmidt lobster optics is proposed. Design study of the optics is presented. The results of experimental tests of the specimen of the optics indicate that the mission is feasible.

Long gamma-ray bursts in the Swift era: the color indices of their optical afterglows

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present an analysis of optical afterglows (OAs) of long GRBs which were mostly discovered by NASA Swift. We used the method of the color indices that uses the commonly available multiband photometry. We show that for most OAs, in the observer frame, these colors, corrected for the reddening inside our Galaxy, display prominent clustering in some color-color diagrams.

New Perspectives in Multispectral Sky Monitoring

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: XI Multifrequency Behaviour of High Energy Cosmic Sources Workshop. Trieste: SISSA/ISAS, 2015. ISSN 1824-8039.
  • Rok: 2015
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    I give a short review and discussion of multispectral (optical and X–rays) sky monitoring.

Optics for Nano-satellite X-Ray Monitor

  • Autoři: Tichý, V., Burrows, D.N., Prieskorn, Z., prof. RNDr. René Hudec, CSc.,
  • Publikace: Baltic Astronomy. 2015, 24(3), 242-250. ISSN 1392-0049.
  • Rok: 2015
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Schmidt lobster eye design for a grazing incidence X-ray optics provides a field of view of the order of many degrees, for this reason it can be a convenient approach for the construction of space X-ray monitors. It is possible to assemble Schmidt lobster eye telescopes with the dimensions and focal lengths acceptable for nano-class satellites. In this paper, a draft of nano-class space mission providing monitoring of specific sky areas is presented. A preliminary optical design study for such mission is performed. Two of possible optical designs are presented, for which the field of view, the effective input area and other basic optical parameters are calculated. Examples of the observed images are also presented.

Preliminary design of optics for nano-satellite monitor

  • Autoři: Tichý, V., prof. RNDr. René Hudec, CSc., RNDr. Vojtěch Šimon, Ph.D.,
  • Publikace: Proc. SPIE 9510, EUV and X-ray Optics: Synergy between Laboratory and Space IV. Prague: SPIE - The International Society for Optical Engineering, 2015. Proceedings of SPIE. vol. 9510. ISSN 0277-786X. ISBN 978-1-62841-631-2.
  • Rok: 2015
  • DOI: 10.1117/12.2178683
  • Odkaz: https://doi.org/10.1117/12.2178683
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Schmidt lobster eye multi-foil optics allows high field of view and it can have small mass and dimensions. It makes the optic usable on small low-cost satellite mission that would permanently monitor selected sky area(s). In the paper, possible optical designs are presented. Presented designs are derived of existing optics specimen, therefore they should be technically feasible.

Study of Cataclysmic Variables with the Satellites LOFT and Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., RNDr. Vojtěch Šimon, Ph.D.,
  • Publikace: THE GOLDEN AGE OF CATACLYSMIC VARIABLES AND RELATED OBJECTS - II. Praha: České vysoké učení technické v Praze, 2015. pp. 297-302. Acta Polytechnica Proceedings. ISSN 2336-5382. ISBN 978-80-01-05688-2.
  • Rok: 2015
  • DOI: 10.14311/APP.2015.02.0297
  • Odkaz: https://doi.org/10.14311/APP.2015.02.0297
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The goal of this paper is to discuss the capabilities of ESA satellite missions Gaia (already in space) and LOFT (considered for the ESA M4 slot) for investigation of cataclysmic variables (CVs). Both Gaia and LOFT can contribute to study of CVs and related objects. Spectrophotometry and low dispersion spectroscopy are the most important for CV analyses with the observations of Gaia. We present the possible strategies for investigation of CVs in the sampled photometric and spectroscopic data provided by Gaia. E.g. statistical properties of the long-term activity of various types of CVs can be determined from them. LOFT can be a promising satellite to provide a sensitive X-ray monitor which will enable to investigate the little studied long-term activity of various types of CVs (especially the magnetic ones) in the X-ray band.

Study of High-z Universe with GAIA and LDS Sky Surveys

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: XI Multifrequency Behaviour of High Energy Cosmic Sources Workshop. Trieste: SISSA/ISAS, 2015. ISSN 1824-8039.
  • Rok: 2015
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on possibilities of study of high z Universe with ESA Gaia satellite and photographic sky surveys with low dispersive spectroscopy

X-ray monitoring for astrophysical applications on Cubesat

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Inneman, A., Černá, D., Jakůbek, J., Ing. Ladislav Sieger, CSc., Dániel, V., Cash, V., Mikulickova, L., Pavlica, R., Belas, E., Polak, J.
  • Publikace: Proc. SPIE 9510, EUV and X-ray Optics: Synergy between Laboratory and Space IV. Prague: SPIE - The International Society for Optical Engineering, 2015. Proceedings of SPIE. vol. 9510. ISSN 0277-786X. ISBN 978-1-62841-631-2.
  • Rok: 2015
  • DOI: 10.1117/12.2185091
  • Odkaz: https://doi.org/10.1117/12.2185091
  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    The primary objective of the project VZLUSAT-1 is the development, manufacturing, qualification and experimental verification of products and technologies in Earth orbit (IOD – In-Orbit Demonstration). This work addresses the issue of X-ray monitoring for astrophysical applications. The proposed wide-field optical system has not been used in space yet. The proposed novel approach is based on the use of 1D "Lobster eye" optics in combination with Timepix X-ray detector in the energy range 3 - 40 keV. The proposed project includes theoretical study and a functional sample of the Timepix X-ray detector with multifoil wide-field X-ray "Lobster eye" optics. Using optics to focus X-rays on a detector is the only solution in cases the intensity of impinging X-ray radiation is below the sensitivity of the detector, e.g. while monitoring astrophysical objects in space, or phenomena in the Earth's atmosphere. On board the functions and features of Radiation Hardened Composite Housing (RHCH), Solar panels based on composite substrate and Hollow Retro Reflector Array based on composite (HRRA) will be verified. To verify the properties of the developed products the satellite is equipped by Health Monitoring system (HM). HM system includes temperature, volatiles, radiation and mechanical properties sensors. The custom ADCS algorithms are being developed within the project. Given the number of IOD experiments and the necessary power the 1U CubeSat is equipped with Composite Deployable Panels (CDP) where HM panels and additional Solar panels are located. Satellite platform is assembled from commercial parts. Mission VZLUSAT-1 is planned for 6 months with launch in 2016.

Accuracy of DSLR cameras

  • Autoři: Skala, P., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astroplate 2014. Praha: VŠCHT, 2014. pp. 70-74. ISBN 978-80-7080-918-1.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper deals with problematic whether is possible to use DSLR (digital single-lens reflex) cameras for precise measurement. Digital cameras have good cost to performance ratio thus they are good candidates as tools for digitalization of astronomy glass plates and photometric measurement. This paper shows what affect output data accuracy of such devices

Algebraic approach to non-separable two-dimensional Schrödinger equation: Ground states for polynomial and Morse-like potentials

  • Autoři: Tichý, V., Skála, L., prof. RNDr. René Hudec, CSc.,
  • Publikace: Central European Journal of Physics. 2014, 12(10), 730-736. ISSN 1895-1082.
  • Rok: 2014
  • DOI: 10.2478/s11534-014-0484-5
  • Odkaz: https://doi.org/10.2478/s11534-014-0484-5
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper presents a direct algebraic method of searching for analytic solutions of the two-dimensional time-independent Schrödinger equation that is impossible to separate into two one-dimensional ones. As examples, two-dimensional polynomial and Morse-like potentials are discussed. Analytic formulas for the ground state wave functions and the corresponding energies are presented. These results cannot be obtained by another known method.

An active state of the BL Lacertae object Markarian 421 detected by INTEGRAL in April 2013

  • Autoři: Pian, E., Turler, M., Fiocchi, M., Boissay, R., Bazzano, A., Foschini, L., Tavecchio, F., Bianchin, V., Castignani, G., Ferrigno, C., Raiteri, C.M., Villata, M., Beckmann, V., D'Ammando, F., prof. RNDr. René Hudec, CSc., Malaguti, G., Maraschi, L., Pursimo, T., Romano, P., Soldi, S., Stamerra, A., Treves, A., Ubertini, P., Vercellone, S., Walter, R.
  • Publikace: Astronomy & Astrophysics. 2014, 570 ISSN 0004-6361.
  • Rok: 2014
  • DOI: 10.1051/0004-6361/201322191
  • Odkaz: https://doi.org/10.1051/0004-6361/201322191
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Multiwavelength variability of blazars offers indirect, but very effective, insight into their powerful engines and on the mechanisms through which energy is propagated from the centre down the jet. The BL Lac object Mkn 421 is a TeV emitter, a bright blazar at all wavelengths, and therefore an excellent target for variability studies. We activated INTEGRAL observations of Mkn 421 in an active state on 16-21 April 2013, and complemented them with Fermi-LAT data. We obtained well sampled optical, soft, and hard X-ray light curves that show the presence of two flares and time-resolved spectra in the 3.5-60 keV (JEM-X and IBIS/ISGRI) and 0.1-100 GeV (Fermi-LAT) ranges.

Digitized Astronomical Photographic Archives as Large Area Sky Survey of Large Amount of Astronomical Data

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Frontier Research in Astrophysics. Trieste: SISSA-The International School for Advanced Studies, 2014. Proceedings of Science. ISSN 1824-8039.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on an investigation of astronomical plate archives and tests of the scanning devices for digitization of archival astronomical plates. These archives represent huge database of historical astronomical data, astrometric, photometric, and spectroscopic, with many applications in modern astrophysics.

GAME: GRB and All-sky Monitor Experiment

  • Autoři: Amati, L., Campana, R., Evangelista, Y., Feroci, M., Fuschino, F., Labanti, C., Salvaterra, R., Stratta, G., Tagliaferri, G., Frontera, F., Guidorzi, C., Rosati, P., Titarchuck, L., Braga, J., Penacchioni, A., Ruffini, R., Izzo, L., Zampa, N., Vacchi, A., Santangelo, A., prof. RNDr. René Hudec, CSc., Gomboc, A., Rodic, T.
  • Publikace: INTERNATIONAL JOURNAL OF MODERN PHYSICS D. 2014, 23(6), ISSN 0218-2718.
  • Rok: 2014
  • DOI: 10.1142/S0218271814300109
  • Odkaz: https://doi.org/10.1142/S0218271814300109
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We describe the GRB and all-sky monitor experiment (GAME) mission submitted by a large international collaboration (Italy, Germany, Czech Republic, Slovenia, Brazil) in response to the 2012 ESA call for a small mission opportunity for a launch in 2017 and presently under further investigation for subsequent opportunities. The general scientific objective is to perform measurements of key importance for GRB science and to provide the wide astrophysical community of an advanced X-ray all-sky monitoring system. The proposed payload was based on silicon drift detectors (similar to 1-50 keV), CdZnTe (CZT) detectors (similar to 15-200 keV) and crystal scintillators in phoswich (NaI/CsI) configuration (similar to 20 keV-20MeV), three well established technologies, for a total weight of similar to 250 kg and a required power of similar to 240 W. Such instrumentation allows a unique, unprecedented and very powerful combination of large field of view (3-4 sr), a broad energy band extending from similar to 1keV up to similar to 20MeV, an energy resolution as good as similar to 250 eV in the 1-30 keV energy range, a source location accuracy of similar to 1 arcmin. The mission profile included a launch (e.g. by Vega) into a low Earth orbit, a baseline sky scanning mode plus pointed observations of regions of particular interest, data transmission to ground via X-band (4.8 Gb/orbit, Alcantara and Malindi ground stations), and prompt transmission of GRB/transient triggers.

GLObal Robotic telescopes Intelligent Array for e-Science

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Frontier Research in Astrophysics. Trieste: SISSA-The International School for Advanced Studies, 2014. Proceedings of Science. ISSN 1824-8039.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on the ongoing EU FP7 Project GLORIA with emphasis on possibility of investigation of cataclysmic variables by users. GLORIA stands for GLObal Robotic-telescopes Intelligent Array. GLORIA enables the first free and open-access network of robotic telescopes in the world. It represents a Web 2.0 environment where users can do research in astronomy by observing with robotic telescopes, and/or by analyzing data that other users have acquired with GLORIA, or from other free access databases like the European Virtual Observatory.

Scientific astrophysical payloads for pico and nano-satellites

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The picosatellites, recently in development at many institutes and universities (e.g. Schmidt et al. 2009 and Schilling 2006), require a miniaturized payload. We present and discuss an idea for a suitable scientific payload, namely a miniature Lobster Eye X-ray telescope.

Sky Monitoring With Lobster

  • Autoři: prof. RNDr. René Hudec, CSc., Tichý, V.
  • Publikace: III Workshop on Robotic Autonomous Observatories. México: Universidad Nacional Autónoma de México, 2014. pp. 143-144. Revista Mexicana de Astronomia y Astrofisica-Serie de Conferencias. ISSN 1405-2059.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The X–ray sky monitoring represents valuable energy spectral extension to optical sky monitoring. Lobster–Eye all–sky monitors are able to provide relatively high sensitivity and good time resolution in the soft X–ray energy range up to 10 keV. The fine time resolution can be used to alert optical robotic telescopes for follow–up and multispectral analyzes in the visible light.

The design of the wide field monitor for LOFT mission

  • Autoři: Brandt, S., Hernanz, M., Alvarez, L., Argan, A., Artigues, B., Azzarello, P., Barret, D., Bozzo, E., Budtz-Jørgensen, C., Campana, R., Cros, A., del Monte, E., Donnarumma, I., Evangelista, Y., Feroci, M., Galvez Sanchez, J.L., Götz, D., Hansen, F., den Herder, J.W., prof. RNDr. René Hudec, CSc., Huovelin, J., Karelin, D., Korpela, S., Lund, N., Michalska, M., Olsen, P., Orleanski, P., Pedersen, S., Pohl, M., Rachevski, A., Santangelo, A., Schanne, S., Schmid, C., Suchy, S., Tenzer, C., Vacchi, A., Walton, D., Wilms, J., Zampa, G., Zampa, N., in't Zand, J., Zane, S., Zdziarski, A., Zwart, F.
  • Publikace: Proceedings of SPIE vol. 9144: Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray. Bellingham: SPIE, 2014, Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9612-6. Available from: http://arxiv.org/ftp/arxiv/papers/1408/1408.6540.pdf
  • Rok: 2014
  • DOI: 10.1117/12.2055885
  • Odkaz: https://doi.org/10.1117/12.2055885
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    LOFT (Large Observatory For x-ray Timing) is one of the ESA M3 missions selected within the Cosmic Vision program in 2011 to carry out an assessment phase study and compete for a launch opportunity in 2022-2024. The phase-A studies of all M3 missions were completed at the end of 2013. LOFT is designed to carry on-board two instruments with sensitivity in the 2-50 keV range: a 10 m 2 class Large Area Detector (LAD) with a <1{deg} collimated FoV and a wide field monitor (WFM) making use of coded masks and providing an instantaneous coverage of more than 1/3 of the sky. The prime goal of the WFM will be to detect transient sources to be observed by the LAD. However, thanks to its unique combination of a wide field of view (FoV) and energy resolution (better than 500 eV), the WFM will be also an excellent monitoring instrument to study the long term variability of many classes of X-ray sources. The WFM consists of 10 independent and identical coded mask cameras arranged in 5 pairs to provide the desired sky coverage. We provide here an overview of the instrument design, configuration, and capabilities of the LOFT WFM. The compact and modular design of the WFM could easily make the instrument concept adaptable for other missions.

The GLObal Robotic telescopes Intelligent Array for E-Science (GLORIA)

  • Autoři: Castro-Tirado, A.J., Sánchez Moreno, F.M., Pérez del Pulgar, C., Azócar, D., Beskin, G., Cabello, J., Cedazo, R., Cuesta, L., Cunniffe, R., Gonzáles, E., Gonzáles-Rodríguez, A., Gorosabel, J., Hanlon, L., prof. RNDr. René Hudec, CSc., Jakubek, M., Janeček, P., Jelínek, M., Lara-Gil, O., Linttot, C., López-Casado, M.C., Malaspina, M., Mankiewicz, L., Maureira, E., Maza, J., Muñoz-Martínez, V.F., Nicastro, L., O'Boyle, E., Palazzi, E., prof. Mgr. Petr Páta, Ph.D. Pio, M.A., Prouza, M., Serena, F., Serra-Ricart, M., Simpson, R., Sprimont, P., Strobl, J., Topinka, M., doc. Ing. Stanislav Vítek, Ph.D. Zarnecki, A.F.
  • Publikace: III Workshop on Robotic Autonomous Observatories. México: Universidad Nacional Autónoma de México, 2014. p. 104-109. Revista Mexicana de Astronomia y Astrofisica-Serie de Conferencias. ISSN 1405-2059.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    GLORIA is a collaborative web-2.0 project based on a network of robotic telescopes, which has become the first free-access network opened to the world for public outreach and specially for e-Science projects.

The large area detector of LOFT: the Large Observatory for X-ray Timing

  • Autoři: Zane, S., Walton, D., Kennedy, T., Feroci, M., den Herder, J.W., Ahangarianabhari, M., Argan, A., Azzarello, P., Baldazzi, G., Barbera, M., Barret, D., Bertuccio, G., Bodin, P., Bozzo, E., Bradley, L., Cadoux, F., Cais, P., Campana, R., Coker, J., Cros, A., del Monte, E., de Rosa, A., di Cosimo, S., Donnarumma, I., Evangelista, Y., Favre, Y., Feldman, C., Fraser, G., Fuschino, F., Grassi, M., Hailey, M.R., prof. RNDr. René Hudec, CSc. Labanti, C., Macera, D., Malcovati, P., Marisaldi, M., Martindale, A., Mineo, T., Muleri, F., Nowak, M., Orlandini, M., Pacciani, L., Perinati, E., Petráček, V., Pohl, M., Rachevski, A., Smith, P., Santangelo, A., Seyler, J.Y., Schmid, C., Soffitta, P., Suchy, S., Tenzer, C., Uttley, P., Vacchi, A., Zampa, G., Zampa, N., Wilms, J., Winter, B.
  • Publikace: Proceedings of SPIE vol. 9144: Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray. Bellingham: SPIE, 2014, Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9612-6. Available from: http://arxiv.org/ftp/arxiv/papers/1408/1408.6539.pdf
  • Rok: 2014
  • DOI: 10.1117/12.2054654
  • Odkaz: https://doi.org/10.1117/12.2054654
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    LOFT (Large Observatory for X-ray Timing) is one of the five candidates that were considered by ESA as an M3 mission (with launch in 2022-2024) and has been studied during an extensive assessment phase. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. Its pointed instrument is the Large Area Detector (LAD), a 10 m2-class instrument operating in the 2-30keV range, which holds the capability to revolutionise studies of variability from X-ray sources on the millisecond time scales. The LAD instrument has now completed the assessment phase but was not down-selected for launch. However, during the assessment, most of the trade-offs have been closed leading to a robust and well documented design that will be reproposed in future ESA calls. In this talk, we will summarize the characteristics of the LAD design and give an overview of the expectations for the instrument capabilities. ˆ (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

The Large Observatory For x-ray Timing

  • Autoři: Feroci, M., den Herder, J.W., Bozzo, E., Barret, D., Brandt, S., Hernanz, M., van der Klis, M., Pohl, M., Santangelo, A., Stella, L., Watts, A., Wilms, J., Zane, S., Ahangarianabhari, M., Albertus, C., Alford, M., Alpar, A., Altamirano, D., Alvarez, L., Amati, L., Amoros, C., Andersson, N., Antonelli, A., Argan, A., prof. RNDr. René Hudec, CSc., Petráček, V.
  • Publikace: Proceedings of SPIE vol. 9144: Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray. Bellingham: SPIE, 2014. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9612-6.
  • Rok: 2014
  • DOI: 10.1117/12.2055913
  • Odkaz: https://doi.org/10.1117/12.2055913
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final downselection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supranuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m2 effective area, 2-30 keV, 240 eV spectral resolution, 1° collimated field of view) and a Wide Field Monitor (WFM, 2-50 keV, 4 steradian field of view, 1 arcmin source location accuracy, 300 eV spectral resolution). The WFM is equipped with an on-board system for bright events (e.g. GRB) localization. The trigger time and position of these events are broadcast to the ground within 30 s from discovery. In this paper we present the status of the mission at the end of its Phase A study.

The Role of Robotic Telescopes and GLORIA in High Energy Astrophysics: Imaging And LDS Spectroscopy

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: III Workshop on Robotic Autonomous Observatories. México: Universidad Nacional Autónoma de México, 2014. pp. 110-113. Revista Mexicana de Astronomia y Astrofisica-Serie de Conferencias. ISSN 1405-2059.
  • Rok: 2014
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss the role of robotic telescopes including GLORIA network in high–energy astrophysics, as well as related strategies. Numerous satellite projects focus on high energy astrophysics from X-rays to gamma-rays, however, a large fraction of objects of high-energy astrophysics emits also optical light, which is, in many cases, variable. The observation of these sources at optical wavelengths can provide valuable inputs for multispectral analysis of various categories of celestial high-energy (HE) sources. The magnitudes of numerous objects are bright and can be hence accessed by robotic ground-based observatories, hence these observations can contribute to investigations and analyses of HE sources. In addition to direct imaging, the Low dispersive spectroscopy (LDS) represent important optional strategy for RTs, taking into account the results from past extended LDS surveys with photographic telescopes/plates.

US Astronomical Photographic Data Archives: Hidden Treasures and Importance for High-Energy Astrophysics

  • Autoři: prof. RNDr. René Hudec, CSc., Hudec, L.
  • Publikace: Acta Polytechnica CTU Proceedings Vol 1, No 1 (2014): FRASCATI WORKSHOP 2013. Praha: České vysoké učení technické v Praze, 2014. pp. 316-319. Acta Polytechnica CTU Proceedings. ISSN 2336-5382.
  • Rok: 2014
  • DOI: 10.14311/APP.2014.01.0316
  • Odkaz: https://doi.org/10.14311/APP.2014.01.0316
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on an ongoing investigation of US astronomical plate archives and tests of the suitability of transportable scanning devices for in situ digitization of archival astronomical plates, with emphasis on application in high-energy astrophysics.

X-ray monitoring for astrophysical applications

  • Autoři: Pína, L., Burrows, D., Cash, W., Černá, D., Gorenstein, P., prof. RNDr. René Hudec, CSc., Inneman, A., Jakůbek, J., Maršíková, V., Ing. Ladislav Sieger, CSc., Tichý, V.
  • Publikace: Proc. SPIE 9207, Advances in X-Ray/EUV Optics and Components IX. Bellingham (stát Washington): SPIE, 2014. Proceedings of SPIE. vol. 9207. ISSN 0277-786X. ISBN 978-1-62841-234-5.
  • Rok: 2014
  • DOI: 10.1117/12.2064726
  • Odkaz: https://doi.org/10.1117/12.2064726
  • Pracoviště: Katedra fyziky, Katedra radioelektroniky
  • Anotace:
    This work addresses the issue of X-ray monitoring for astrophysical applications. The proposed wide-field optical system has not been used in space yet. The proposed novel approach is based on the use of 1D "Lobster eye" optics in combination with Timepix X-ray detector in the energy range 3-40 keV. The proposed project includes theoretical study and a functional sample of the Timepix X-ray detector with multifoil wide-field X-ray "Lobster eye" optics. Using optics to focus X-rays on a detector is the only solution in cases the intensity of impinging X-ray radiation is below the sensitivity of the detector, e. g. while monitoring astrophysical objects in space, or phenomena in the Earth's atmosphere. The optical system could be used in a student rocket experiment at University of Colorado. Ideal opportunity is to extend the CubeSat of Pennsylvania State University with the hard X-ray telescope demonstrator consisting of an optical module and Timepix detector.

Active X-ray optics

  • Autoři: prof. RNDr. René Hudec, CSc., Inneman, A., Pína, L., Černá, D., Tichý, V.
  • Publikace: Proceedings of SPIE Vol. 8777 Damage to VUV, EUV, and X-ray Optics IV; and EUV and X-ray Optics: Synergy between Laboratory and Space III. Bellingham (stát Washington): SPIE, 2013. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9579-2.
  • Rok: 2013
  • DOI: 10.1117/12.2021469
  • Odkaz: https://doi.org/10.1117/12.2021469
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In this work, we investigate a novel design of optical system for astrophysics. In addition, a new testing method in the X-ray laboratory was verified. The proposed optical system is composed of modules with Kirkpatrick-Baez configuration allowing usage of multi-foil mirrors arranged to parabolic profile. This system effectively uses a circular aperture, which is divided into petals. Individual petals consist of diagonally oriented KB cells with common focus. The hybrid optical system includes a set of rotationally symmetrical parabolic mirrors to achieve higher reflection efficiency of harder X-rays. New results are presented.

Astronomical plate archives and supermassive black hole binaries

  • DOI: 10.14311/AP.2013.53.0601
  • Odkaz: https://doi.org/10.14311/AP.2013.53.0601
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The recent extensive digitisation of astronomical photographic plate archives, the development of new dedicated software and the use of powerful computers have for the first time enabled effective data mining in extensive plate databases, with wide applications in various fields of recent astrophysics. As an example, analyses of supermassive binary black holes (binary blazars) require very long time intervals (50 years and more), which cannot be provided by other data sources. Examples of data obtained from data mining in plate archives are presented and briefly discussed.

Classification of Variable Objects for Search for GRB Candidates on Bamberg Photographic Plates

  • Autoři: prof. RNDr. René Hudec, CSc., Kopel, F., Macsics, R., Hadwige, M., Heber, U., Caye, W.
  • Publikace: Acta Polytechnica. 2013, 53(1), 27-29. ISSN 1210-2709.
  • Rok: 2013
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on an ongoing study based on blink-comparison of more than 5000 Bamberg Observatory Southern Sky Patrol Plates performed within a continuation of a student high school project (Jugend Forscht). After a detailed analyses and classification, 6 non-classified objects were identified as emulsion defects, 19 as asteroids, 37 as variable stars, and 6 as real OT-GRB candidates

Color indices of optical afterglows of long GRBs in the Swift era

  • Autoři: RNDr. Vojtěch Šimon, Ph.D., Pizzichini, G., prof. RNDr. René Hudec, CSc.,
  • Publikace: Gamma-ray Bursts: 15 Years of GRB Afterglows – Progenitors, Environments and Host Galaxies from the Nearby to the Early Universe. Les Ulis: EDP Sciences, 2013. pp. 271-273. EAS Publications Series. ISSN 1633-4760. ISBN 978-2-7598-1002-4.
  • Rok: 2013
  • DOI: 10.1051/eas/1361043
  • Odkaz: https://doi.org/10.1051/eas/1361043
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We show the power of the method of the color indices that uses the commonly available multiband photometry of optical afterglows (OAs) of long GRBs detected by Swift. Our study shows that for most OAs, in the observer frame, these colors, corrected for the Galactic reddening, display prominent clustering in the color-color diagrams. The color indices enable us to distinguish OAs from other types of objects even without available gamma-ray emission. The color-color diagrams can be used to assess the extinction inside the host galaxy. Our approach is also generally important for investigating the numerous faint OAs for which obtaining spectra with good S/N ratio is often impossible.

Compact low resolution spectrograph, an imaging and long slit spectrograph for robotic telescopes

  • Autoři: Rabaza, O., Jelinek, M., Castro-Tirado, A.J., Cunniffe, R., Zeman, J., prof. RNDr. René Hudec, CSc., Sabau-Graziati, L., Ruedas-Sánchez, J.
  • Publikace: Review of Scientific Instruments. 2013, 84(11), 1-9. ISSN 0034-6748.
  • Rok: 2013
  • DOI: 10.1063/1.4827895
  • Odkaz: https://doi.org/10.1063/1.4827895
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The COmpact LOw REsolution Spectrograph (COLORES) is a compact and lightweight (13 kg) f/8 imaging spectrograph designed for robotic telescopes, now installed and operating on the TELMA, a rapid-slewing 60 cm telescope of the BOOTES-2 observatory in Málaga (Spain). COLORES is a multi-mode instrument that enables the observer to seamlessly switch between low-dispersion spectroscopy and direct imaging modes during an observation. In this paper, we describe the instrument and its development, from the initial scientific requirements through the optical design process to final configuration with theoretical performance calculations. The mechanical and electronic design is described, methods of calibration are discussed and early laboratory and scientific results are shown.

Czech Contribution to LOFT

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We describe the current status of the Czech contribution to the ESA LOFT space mission, with emphasis on technical aspects. Expertise available in the Czech Republic will play a positive role in the LOFT project and related developments.

Design of novel X-ray optical system for rocket experiment

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Tichý, V., Inneman, A., Cerna, D., Švéda, L., Marsik, J., Marsikova, V., Cash, W., Shipley, A.F., Zeiger, B.R., Rogers, T.D.
  • Publikace: Proceedings of SPIE Vol. 8848 Advances in X-Ray/EUV Optics and Components VIII. Bellingham (stát Washington): SPIE, 2013. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9698-0.
  • Rok: 2013
  • DOI: 10.1117/12.2023984
  • Odkaz: https://doi.org/10.1117/12.2023984
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A novel design of X-ray optical system - concentrator for astrophysical rocket experiment is investigated. The proposed system is based on four modules with Kirkpatrick-Baez (KB) configuration allowing usage of multi-foil mirrors arranged to parabolic profile. The KB modules are supplemented by rotationally symmetrical parabolic segments. This X-ray optical system effectively uses a circular aperture. The KB modules are placed in four quadrants while the segments are set into a Cartesian cross between the KB modules. Studied optical system is under consideration for the student rocket experiment of University of Colorado that should verify function of NIST's energy-dispersive detector based on Transition Edge Sensors (TES microcalorimeters).

Finding Hidden Treasures: Investigations in US Astronomical Plate Archives

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report here on an ongoing investigation of US astronomical plate archives and tests of the suitability of transportable scanning devices for in situ digitization of archival astronomical plates.

GRB INVESTIGATIONS BY ESA GAIA AND LOFT

  • DOI: 10.14311/AP.2013.53.0799
  • Odkaz: https://doi.org/10.14311/AP.2013.53.0799
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The possibility of studying GRBs with the ESA Gaia and LOFT missions is briefly addressed. The ESA Gaia satellite to be launched in November 2013 will focus on high precision astrometry of stars and all objects down to limiting magnitude 20. The satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics, including the study of GRBs and related optical afterglows (OAs) and optical transients (OTs). The strength of Gaia in GRB analyses will be the fine spectral resolution (spectro-photometry and ultra-low dispersion spectroscopy), which will allow the correct classication of related triggers. An interesting feature of Gaia BP and RP instruments will be the study of highly redshifted triggers. Similarly, the low dispersion spectroscopy provided by various plate surveys can also supply valuable data for investigations of high-energy sources. The ESA LOFT candidate mission, now in the assessment study phase, will also be able to detect and be used in the study of GRBs, with emphasis on low-energy (X-ray) emission

GRB Potential of ESA Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., RNDr. Vojtěch Šimon, Ph.D.,
  • Publikace: Gamma-ray Bursts: 15 Years of GRB Afterglows – Progenitors, Environments and Host Galaxies from the Nearby to the Early Universe. Les Ulis: EDP Sciences, 2013. pp. 639-643. EAS Publications Series. ISSN 1633-4760. ISBN 978-2-7598-1002-4.
  • Rok: 2013

GRBs and Lobster Eye X-Ray Telescopes

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Marsikova, V., Inneman, A.
  • Publikace: Gamma-ray Bursts: 15 Years of GRB Afterglows – Progenitors, Environments and Host Galaxies from the Nearby to the Early Universe. Les Ulis: EDP Sciences, 2013. pp. 611-615. EAS Publications Series. ISSN 1633-4760. ISBN 978-2-7598-1002-4.
  • Rok: 2013
  • DOI: 10.1051/eas/1361097
  • Odkaz: https://doi.org/10.1051/eas/1361097
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A large majority of GRBs exhibit X-ray emission. In addition, a dedicated separate group of GRB, the XRFs, exists which emission dominates in the X-ray spectral range. And the third group of GRB related objects (yet hypothetical) are the group of off-axis observed GRBs (orphan afterglows). These facts justify the consideration of an independent experiment for monitoring, detection and analyses of GRBs and others fast X-ray transients in X-rays. We will present and discuss such experiment based on wide-field X-ray telescopes of Lobster Eye type. We show that the wide field and fine sensitivity of Lobster Eye X-ray All-Sky Monitor make such instruments important tools in study of GRBs.

GRBS Followed-up by the BOOTES network

  • Autoři: Guziy, S., Castro-Tirado, A., Jelínek, M., Gorosabel, J., Kubánek, P., Cunniffe, R., prof. RNDr. René Hudec, CSc., doc. Ing. Stanislav Vítek, Ph.D.,
  • Publikace: Gamma-ray Bursts: 15 Years of GRB Afterglows – Progenitors, Environments and Host Galaxies from the Nearby to the Early Universe. Les Ulis: EDP Sciences, 2013. pp. 251-254. EAS Publications Series. ISSN 1633-4760. ISBN 978-2-7598-1002-4.
  • Rok: 2013
  • DOI: 10.1051/eas/1361038
  • Odkaz: https://doi.org/10.1051/eas/1361038
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Burst Observer and Optical Transient Exploring System (BOOTES), is a global robotic observatory network, which started in 1998 with Spanish leadership devoted to study optical emissions from gamma ray bursts (GRBs) that occur in the Universe. We present shot history and current status of BOOTES network. The Network philosophy, science and some details of 117 GRBs followed-up are discussed.

Hybrid X-ray optical system for space astrophysics

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Tichý, V., Inneman, A., Černá, D., Marsik, J., Marsikova, V., Cash, W., Shipley, A.F., Zeiger, B.R., Rogers, T.D.
  • Publikace: Proceedings of SPIE Vol. 8777 Damage to VUV, EUV, and X-ray Optics IV; and EUV and X-ray Optics: Synergy between Laboratory and Space III. Bellingham (stát Washington): SPIE, 2013. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9579-2.
  • Rok: 2013
  • DOI: 10.1117/12.2017205
  • Odkaz: https://doi.org/10.1117/12.2017205
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In this work, we investigate a novel design of optical system for astrophysics. In addition, a new testing method in the X-ray laboratory was verified. The proposed optical system is composed of modules with Kirkpatrick-Baez configuration allowing usage of multi-foil mirrors arranged to parabolic profile. This system effectively uses a circular aperture, which is divided into petals. Individual petals consist of diagonally oriented KB cells with common focus. The hybrid optical system includes a set of rotationally symmetrical parabolic mirrors to achieve higher reflection efficiency of harder X-rays. New results are presented.

NANOX: proposed Nano-Satellite X-Ray Mission

  • Autoři: Tichý, V., RNDr. Vojtěch Šimon, Ph.D., prof. RNDr. René Hudec, CSc., Inneman, A., Burrows, D.N.
  • Publikace: Proceedings of SPIE Vol. 8777 Damage to VUV, EUV, and X-ray Optics IV; and EUV and X-ray Optics: Synergy between Laboratory and Space III. Bellingham (stát Washington): SPIE, 2013. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9579-2.
  • Rok: 2013
  • DOI: 10.1117/12.2017612
  • Odkaz: https://doi.org/10.1117/12.2017612
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present the idea of a low-cost satellite providing permanent monitoring of X-ray binaries. These systems contain a compact object (a neutron star or a black hole) accreting matter from a donor companion. They concentrate in the vicinity of the Galactic plane and toward the center of the Galaxy. It therefore appears very advantageous to point the telescope toward the Galactic center. The strong activity of X-ray binaries with non-predictable episodes of brightening suggests that we can obtain meaningful and physically important information even by a study using a small, inexpensive satellite. The proposed spacecraft can be of the nano-satellite class. We propose Schmidt lobster optics for this satellite. The results of experimental tests of the specimen of such optics show that the mission is feasible.

Observing GRBs with the LOFT Wide Field Monitor

  • Autoři: Brandt, S., Hernanz, M., Feroci, M., Amati, L., Alvarez, A., Azzarello, P., prof. RNDr. René Hudec, CSc.,
  • Publikace: Gamma-ray Bursts: 15 Years of GRB Afterglows – Progenitors, Environments and Host Galaxies from the Nearby to the Early Universe. Les Ulis: EDP Sciences, 2013. pp. 617-623. EAS Publications Series. ISSN 1633-4760. ISBN 978-2-7598-1002-4.
  • Rok: 2013
  • DOI: 10.1051/eas/1361098
  • Odkaz: https://doi.org/10.1051/eas/1361098
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    LOFT (Large Observatory For X-ray Timing) is one of the four candidate missions currently under assessment study for the M3 mission in ESAs Cosmic Vision program to be launched in 2024. LOFT will carry two instruments with prime sensitivity in the 2-30 keV range: a 10 m(2) class large area detector (LAD) with a <1 degrees collimated field of view and a wide field monitor (WFM) instrument. The WFM is based on the coded mask principle, and 5 camera units will provide coverage of more than 1/3 of the sky. The prime goal of the WFM is to detect transient sources to be observed by the LAD. With its wide field of view and good energy resolution of <500 eV, the WFM will be an excellent instrument for detecting and studying GRBs and X-ray flashes. The WFM will be able to detect similar to 150 gamma ray bursts per year, and a burst alert system will enable the distribution of similar to 100 GRB positions per year with a similar to 1 arcmin location accuracy within 30 s of the burst.

The Czech Contribution to Future Large X-Ray Astronomy Telescopes: Recent Progress

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Inneman, A., Černá, D., Maršíková, V., Tichý, V., Míka, M.
  • Publikace: Acta Polytechnica. 2013, 53(1), 33-37. ISSN 1210-2709.
  • Rok: 2013
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We briefly review the recent status of the Czech contribution to future space X-ray astronomy missions with emphasis on the development of new technologies and test samples of X-ray mirrors with precise surfaces based on new materials and alternative designs. We report on further investigations and tests of X-ray optical arrangements, such as Kirkpatrick-Baez systems and Multi-Foil Optics.

The historical 1900 and 1913 outbursts of the binary blazar candidate OJ287

  • Autoři: prof. RNDr. René Hudec, CSc., Bašta, M., Pihajoki, P., Valtonen, M.
  • Publikace: Astronomy & Astrophysics. 2013, 559 ISSN 0004-6361.
  • Rok: 2013
  • DOI: 10.1051/0004-6361/201219323
  • Odkaz: https://doi.org/10.1051/0004-6361/201219323
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on historical optical outbursts in the OJ287 system in 1900 and 1913, detected on archival astronomical plates of the Harvard College Observatory. The 1900 outburst is reported for the first time. The first recorded outburst of the periodically active quasar OJ287 described before was observed in 1913. Up to now the information on this event was based on three points from plate archives. We used the Harvard plate collection, and added another seven observations to the light curve. The light curve is now well covered and allows one to determine the beginning of the outburst quite accurately. The outburst was longer and more energetic than the standard 1983 outburst. Should the system be strictly periodic, the period determined from these two outbursts would be 11.665 yr. However, this does not match the 1900 outburst or other prominent outbursts in the record. On the other hand, the precessing binary black hole model of Lehto and Valtonen (1996) can explain these and other known outbursts in OJ287. Finally, we discuss the upper limits for the expected 1906 outburst and the 1910 outburst, which was observed.

A Large Area Detector proposed for the Large Observatory for X-ray Timing (LOFT)

  • Autoři: Zane, S., Walton, D., Kennedy, T., Feroci, M., den Herder, J.-W.A., prof. RNDr. René Hudec, CSc., Petráček, V.
  • Publikace: SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY. Washington: SPIE - The International Society for Optical Engineering, 2012. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9144-2.
  • Rok: 2012
  • DOI: 10.1117/12.925156
  • Odkaz: https://doi.org/10.1117/12.925156
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The Large Observatory for X-ray Timing (LOFT) is one of the four candidate ESA M3 missions considered for launch in the 2022 timeframe. It is specifically designed to perform fast X-ray timing and probe the status of the matter near black holes and neutron stars. The LOFT scientific payload is composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD is a 10 m(2)-class pointed instrument with 20 times the collecting area of the best past timing missions (such as RXTE) over the 2-30 keV range, which holds the capability to revolutionize studies of X-ray variability down to the millisecond time scales. Its ground-breaking characteristic is a low mass per unit surface, enabling an effective area of similar to 10 m(2) (@10 keV) at a reasonable weight. The development of such large but light experiment, with low mass and power per unit area, is now made possible by the recent advancements in the field of large-area silicon detectors - able to time tag an X-ray photon with an accuracy <10 mu s and an energy resolution of similar to 260 eV at 6 keV - and capillary-plate X-ray collimators. In this paper, we will summarize the characteristics of the LAD instrument and give an overview of its capabilities.

Astrophysics of cataclysmic variables by ESA Gaia and low dispersion spectroscopy

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudec, L., Hudcová, V.
  • Publikace: MEMORIE della Societa Astronomica Italiana. 2012, 83(2), 849-853. ISSN 1824-016X.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss the study related to the ESA satellite Gaia to be launched in 2013 with focus on the high precision astrometry of stars and all objects down to limiting magnitude 20. The satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics including study of cataclysmic variables. The strength of Gaia in such analyzes is the fine spectral resolution (spectro-photometry and ultra-low dispersion spectroscopy) which will allow the correct classication of related objects. The low dispersion spectroscopy provided by various plate surveys can also provide valuable data for investigation of cataclysmic variables.

BOOTES Observation of GRB 080603B

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on multicolor photometry of long GRB080603B afterglow from BOOTES-1B and BOOTES-2. The optical afterglow has already been reported to present a break in the optical lightcurve at 0.12 ± 0.2 days after the trigger. We construct the lightcurve and the spectral energy distribution and discuss the nature of the afterglow.

Cycles in the cataclysmic variable V795 Herculis

  • Autoři: Simon, V., Polasek, C., Strobl, J., prof. RNDr. René Hudec, CSc., Blažek, M.
  • Publikace: Astronomy & Astrophysics. 2012, 540(540), ISSN 0004-6361.
  • Rok: 2012
  • DOI: 10.1051/0004-6361/201118508
  • Odkaz: https://doi.org/10.1051/0004-6361/201118508
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We investigate the photometric activity of the cataclysmic variable (CV) V795 Her. We pay attention to the time evolution of the length of its superhump cycle Psh. We investigate how well the superhump profile is reproduced in the individual phases Φsh of Psh. We also analyze the mutual relation of the intensity of the superhump light and the superimposed rapid intensity variations. Methods: We used the photometric V-band CCD observations obtained between 2008 and 2010. The observing run on a given night consisted of a dense series of V-band images (exp. time of 20 s), which enabled us to investigate the superhump profile and the superimposed rapid changes.

ESA Gaia & the multifrequency behavior of high-energy sources with ultra-low dispersion spectroscopy

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudec, L., Hudcová, V.
  • Publikace: Workshop on multifrequency behaviour of high energy cosmic sources. Roma: Societa Astronomica Italiana, 2012. pp. 342-346. Memorie della Societa Astronomica Italiana, Supplementi. ISSN 1824-0178.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss the project related to the ESA satellite Gaia to be launched in 2013 with focus on the high precision astrometry of stars and all objects down to limiting magnitude 20. The satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics including study of high-energy sources. The strength of Gaia in such analyzes is the fine spectral resolution (spectro-photometry and ultra-low dispersion spectroscopy) which will allow the correct classication of related triggers. The low dispersion spectroscopy provided by various plate surveys can also provide valuable data for investigation of high-energy sources.

ESA Gaia, ultra-low dispersion spectroscopy and GRBs

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V.
  • Publikace: GRBs as probes from the progenitors environment to the high redshift Universe. Roma: Societa Astronomica Italiana, 2012. pp. 186-189. Memorie della Societa Astronomica Italiana, Supplementi. ISSN 1824-0178.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ESA satellite Gaia to be launched in 2013 will focus on precise astrometry of stars down to magnitude 20. The satellite will also provide photometric and spectral information for various branches of astrophysics including GRB science. The strength of Gaia in such analyzes is the fine spectral resolution (spectro-photometry and ultra-low dispersion spectroscopy) The possibilities to detect and to analyze optical transients and optical afterglows of GRBs by Gaia, both based on photometry as well as spectrophotometry and low-dispersion spectroscopy, are discussed.

Golden Era of Cataclysmic Variables and Related Objects: concluding remarks

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The cataclysmic variables represent important part of modern astrophysics, as demonstrated by the conference Golden Era of Cataclysmic Variables and Related Objects held on Mondello (Palermo) in September 2011.

GRIPS - Gamma-Ray Imaging, Polarimetry and Spectroscopy

  • Autoři: Greiner, J., Mannheim, K., Aharonian, F., Ajello, M., Balasz, L.G., Barbiellini, G., Bellazzini, R., Bishop, S., Bisnovatij-Kogan, G.S., Boggs, S., Bykov, A., DiCocco, G., Diehl, R., Elsässer, D., prof. RNDr. René Hudec, CSc.,
  • Publikace: EXPERIMENTAL ASTRONOMY. 2012, 34(2), 551-582. ISSN 0922-6435.
  • Rok: 2012
  • DOI: 10.1007/s10686-011-9255-0
  • Odkaz: https://doi.org/10.1007/s10686-011-9255-0
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We propose to perform a continuously scanning all-sky survey from 200 keV to 80 MeV achieving a sensitivity which is better by a factor of 40 or more compared to the previous missions in this energy range (COMPTEL, INTEGRAL; see Fig. 1). These gamma-ray observations will be complemented by observations in the soft X-ray and (near-)infrared region with the corresponding telescopes placed on a separate satellite. The Gamma-Ray Imaging, Polarimetry and Spectroscopy ("GRIPS") mission with its three instruments Gamma-Ray Monitor (GRM), X-Ray Monitor (XRM) and InfraRed Telescope (IRT) addresses fundamental questions in ESA's Cosmic Vision plan. Among the major themes of the strategic plan, GRIPS has its focus on the evolving, violent Universe, exploring a unique energy window. We propose to investigate γ-ray bursts and blazars, the mechanisms behind supernova explosions, nucleosynthesis and spallation, the enigmatic origin of positrons in our Galaxy, and the nature of radiation processes and particle acceleration in extreme cosmic sources including pulsars and magnetars. The natural energy scale for these non-thermal processes is of the order of MeV. Although they can be partially and indirectly studied using other methods, only the proposed GRIPS measurements will provide direct access to their primary photons. GRIPS will be a driver for the study of transient sources in the era of neutrino and gravitational wave observatories such as IceCUBE and LISA, establishing a new type of diagnostics in relativistic and nuclear astrophysics. This will support extrapolations to investigate star formation, galaxy evolution, and black hole formation at high redshifts.

Investigations of cataclysmic variables by ESA INTEGRAL

  • Autoři: prof. RNDr. René Hudec, CSc., Blažek, M.
  • Publikace: MEMORIE della Societa Astronomica Italiana. 2012, 83(2), 659-664. ISSN 1824-016X.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The results of investigations of cataclysmic variables with the ESA INTEGRAL satellite are briefly presented and discussed. It is evident that the satellite serves as an effi- cient tool to study some of these objects, e.g. cataclysmic variables containing a magnetic white dwarf.

Lobster-eye X-ray monitors: astrophysical aspects

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Tichý, V.
  • Publikace: Workshop on multifrequency behaviour of high energy cosmic sources. Roma: Societa Astronomica Italiana, 2012. pp. 365-369. Memorie della Societa Astronomica Italiana, Supplementi. ISSN 1824-0178.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss the recent progress in design of wide field X-ray monitors with Lobster-eye X-ray optics, with emphasis on astrophysical aspects and justification.

LOFT - the Large Observatory For x-ray Timing

  • Autoři: Feroci, M., den Herder, J.-W.A., Bozzo, E., Barret, D., Brandt, S., prof. RNDr. René Hudec, CSc., Petráček, V.
  • Publikace: SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY. Washington: SPIE - The International Society for Optical Engineering, 2012. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9144-2.
  • Rok: 2012
  • DOI: 10.1117/12.926310
  • Odkaz: https://doi.org/10.1117/12.926310
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The LOFT mission concept is one of four candidates selected by ESA for the M3 launch opportunity as Medium Size missions of the Cosmic Vision programme. The launch window is currently planned for between 2022 and 2024. LOFT is designed to exploit the diagnostics of rapid X-ray flux and spectral variability that directly probe the motion of matter down to distances very close to black holes and neutron stars, as well as the physical state of ultradense matter. These primary science goals will be addressed by a payload composed of a Large Area Detector (LAD) and a Wide Field Monitor (WFM). The LAD is a collimated (<1 degree field of view) experiment operating in the energy range 2-50 keV, with a 10 m(2) peak effective area and an energy resolution of 260 eV at 6 keV. The WFM will operate in the same energy range as the LAD, enabling simultaneous monitoring of a few-steradian wide field of view, with an angular resolution of <5 arcmin. The LAD and WFM experiments will allow us to investigate variability from submillisecond QPO's to yearlong transient outbursts. In this paper we report the current status of the project.

Novel design of a large X-ray optical system for astrophysical application

  • Autoři: Pína, L., prof. RNDr. René Hudec, CSc., Tichý, V., Inneman, A., Černá, D., Maršík, J., Maršíková, V., Cash, W., Shipley, A.F., Zeiger, B.R., Rogers, T.D., Melich, R.
  • Publikace: ADVANCES IN X-RAY/EUV OPTICS AND COMPONENTS VII. Bellingham: SPIE, 2012. pp. 85020D-1-85020D-6. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9219-7.
  • Rok: 2012
  • DOI: 10.1117/12.929591
  • Odkaz: https://doi.org/10.1117/12.929591
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    In this work, we investigate a novel design of optical system for astrophysics. In addition, a new testing method in the X-ray laboratory was verified. The proposed optical system is composed of modules with Kirkpatrick-Baez configuration allowing usage of multi-foil mirrors arranged along a parabolic profile. This system effectively uses a circular aperture, which is divided into petals. Individual petals consist of diagonally oriented KB cells with a common focus. This optical system can be improved by a set of nested rotationally symmetric X-ray mirrors in order to achieve higher reflection efficiency in harder part of considered spectrum.

Outburst and flares from the unique source SWIFT J1955+2614

  • Autoři: Šimon, V., prof. RNDr. René Hudec, CSc., Castro-Tirado, A.J., de Ugarte Postigo, A., Gorosabel, J., Jelínek, M., Fatkhullin, T., Pérez-Ramírez, D., Kubánek, P., Guziy, S., Munoz Darías, T., Cunniffe, R.
  • Publikace: Monthly Notices of the Royal Astronomical Society. 2012, 422(2), 981-989. ISSN 0035-8711.
  • Rok: 2012
  • DOI: 10.1111/j.1365-2966.2012.20668.x
  • Odkaz: https://doi.org/10.1111/j.1365-2966.2012.20668.x
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present results of our analysis of the optical emission of the unique source GRB 070610/SWIFT J195509+261406 during its 2007 outburst and discuss the implications of the non-detection of the very faint optical counterpart in quiescence. We analyse the statistical properties of the optical brightness and X-ray intensity during the outburst and determined an approximate value of the mean colour index R-I. The optical emission has the form of spikes whose duration decreases with the outburst's progress, and the spectral energy distribution from the X-ray to the optical bands undergoes variations during the spikes. We show that the optical emission can be explained by a synchrotron mechanism while any thermal component is below the detection limit. We discuss the similarities between synchrotron emission of J1955 and the optical afterglows (OAs) of the extragalactic long gamma-ray bursts. We conclude that while the emission mechanisms in J1955 and OAs are quite similar, the configurations of their light-emitting regions largely differ. The synchrotron emission of the spike must be primarily generated near (several times 1010 cm) the central object, and cannot be explained by density enhancements in the interstellar medium. We argue that the activity of a central engine plays a great role in generating the afterglow emission of J1955. We discuss the possibility that J1955 is an ultracompact binary with a very low time-averaged mass transfer rate on to the neutron star. This can fulfil the conditions required for J1955, with the 2007 outburst as the extreme case seen from the very close X-ray binary SAX J1808.4-3658 in 2005.

REMOTES: reliable and modular telescope solution for seamless operation and monitoring of various observation facilities

  • Autoři: Jakubec, M., Skala, P., Sedlacek, M., Nekola, M., Strobl, J., Blažek, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Software and Cyberinfrastructure for Astronomy II. Washington: SPIE - The International Society for Optical Engineering, 2012. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9152-7.
  • Rok: 2012
  • DOI: 10.1117/12.926414
  • Odkaz: https://doi.org/10.1117/12.926414
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Astronomers often need to put several pieces of equipment together and have to deploy them at a particular location. This task could prove to be a really tough challenge, especially for distant observing facilities with intricate operating conditions, poor communication infrastructure and unreliable power source. To have this task even more complicated, they also expect secure and reliable operation in both attended and unattended mode, comfortable software with user-friendly interface and full supervision over the observation site at all times. During reconstruction of the D50 robotic telescope facility, we faced many of the issues mentioned above. To get rid of them, we based our solution on a flexible group of hardware modules controlling the equipment of the observation site, connected together by the Ethernet network and orchestrated by our management software. This approach is both affordable and powerful enough to fulfill all of the observation requirements at the same time. We quickly figured out that the outcome of this project could also be useful for other observation facilities, because they are probably facing the same issues we have solved during our project. In this contribution, we will point out the key features and benefits of the solution for observers. We will demonstrate how the solution works at our observing location. We will also discuss typical management and maintenance scenarios and how we have supported them in our solution. Finally, the overall architecture and technical aspects of the solution will be presented and particular design and technology decisions will be clarified.

The Large Observatory for X-ray Timing (LOFT)

  • Autoři: Feroci, M., Stella, L., van der Klis, M., Courvoisier, T.J.-L., Hernanz, M., prof. RNDr. René Hudec, CSc., Petráček, V.
  • Publikace: EXPERIMENTAL ASTRONOMY. 2012, 34(2), 415-444. ISSN 0922-6435.
  • Rok: 2012
  • DOI: 10.1007/s10686-011-9237-2
  • Odkaz: https://doi.org/10.1007/s10686-011-9237-2
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    High-time-resolution X-ray observations of compact objects provide direct access to strong-field gravity, to the equation of state of ultradense matter and to black hole masses and spins. A 10 m(2)-class instrument in combination with good spectral resolution is required to exploit the relevant diagnostics and answer two of the fundamental questions of the European Space Agency (ESA) Cosmic Vision Theme "Matter under extreme conditions", namely: does matter orbiting close to the event horizon follow the predictions of general relativity? What is the equation of state of matter in neutron stars? The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionise the study of collapsed objects in our galaxy and of the brightest supermassive black holes in active galactic nuclei.

The LOFT Wide Field Monitor

  • Autoři: Brandt, S., Hernanz, M., Alvarez, L., Azzarello, P., Barret, D., prof. RNDr. René Hudec, CSc.,
  • Publikace: SPACE TELESCOPES AND INSTRUMENTATION 2012: ULTRAVIOLET TO GAMMA RAY. Washington: SPIE - The International Society for Optical Engineering, 2012, Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-9144-2.
  • Rok: 2012
  • DOI: 10.1117/12.926060
  • Odkaz: https://doi.org/10.1117/12.926060
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    LOFT (Large Observatory For x-ray Timing) is one of the four missions selected in 2011 for assessment study for the ESA M3 mission in the Cosmic Vision program, expected to be launched in 2024. The LOFT mission will carry two instruments with their prime sensitivity in the 2-30 keV range: a 10 m(2) class large area detector (LAD) with a <1 degrees collimated field of view and a wide field monitor (WFM) instrument based on the coded mask principle, providing coverage of more than 1/3 of the sky. The LAD will provide an effective area similar to 20 times larger than any previous mission and will by timing studies be able to address fundamental questions about strong gravity in the vicinity of black holes and the equation of state of nuclear matter in neutron stars. The prime goal of the WFM will be to detect transient sources to be observed by the LAD. However, with its wide field of view and good energy resolution of <300 eV, the WFM will be an excellent monitoring instrument to study long term variability of many classes of X-ray sources. The sensitivity of the WFM will be 2.1 mCrab in a one day observation, and 270 mCrab in 3s in observations of in the crowded field of the Galactic Center. The high duty cycle of the instrument will make it an ideal detector of fast transient phenomena, like X-ray bursters, soft gamma repeaters, terrestrial gamma flashes, and not least provide unique capabilities in the study of gamma ray bursts. A dedicated burst alert system will enable the distribution to the community of similar to 100 gamma ray burst positions per year with a similar to 1 arcmin location accuracy within 30 s of the burst. This paper provides an overview of the design, configuration, and capabilities of the LOFT WFM instrument.

The Optical Transient Search in the Bamberg Southern Sky Survey: Preliminary Results

  • Autoři: prof. RNDr. René Hudec, CSc., Kopel, F., Krapp, P., Heber, U., Caye, W.
  • Publikace: Acta Polytechnica. 2012, 52(1), 23-26. ISSN 1210-2709.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A large fraction of gamma-ray bursts temporarily emit optical light, i.e. optical afterglows and optical transients. So far, optical transients have only been detected after related gamma-ray satellite detection. However, taking into account their optical magnitudes at maximum light, these objects should be detectable in various historical and recent optical surveys, including the photographic sky patrol. Here we report on an extended study based on blink-comparison of 5004 Bamberg Observatory Southern Sky Patrol Plates performed within a student high school project (Jugend Forscht).

The role of Robotic telescopes in space astronomy

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: Second Workshop on Robotic Autonomous Observatories. Bengaluru: Astronomical Society of India, 2012. pp. 209-218. Astronomical Society of India Conference Series. ISBN 978-81-922926-5-6.
  • Rok: 2012
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss the role of robotic telescopes in satellite projects, as well as related strategies. Numerous satellite projects in space astrophysics focus on high energy astrophysics from X-rays to gammarays. However, a large fraction of objects of high-energy astrophysics emit also optical light, which in many cases, are variables. The observation of these sources at optical wavelengths can provide valuable inputs for multispectral analysis of various categories of celestial high-energy (HE) sources. There are also satellite projects outside the high–energy astronomy, in which the robotic telescopes can also play an important role, e.g. the ESA satellite Gaia. In Gaia, robotic telescopes are expected to verify the triggers detected by satellite (such as transients and flares) but also to provide additional (mostly photometric) data for better scientific cases.

Ultra Low Dispersion Spectroscopy with Gaia and Astronomical Slitless Surveys

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ultra-low dispersion spectroscopy to be applied in the ESA Gaia space observatory and the ground-based objective-prism plate surveys represent a similar type of astrophysical data. Although the dispersion in plate surveys is usually larger than in the Gaia blue and red photometers (BP/RP), the spectral resolutions differ by a factor of 2-3 only, since the resolution in ground-based spectra is seeing-limited. We argue that some of the algorithms developed for digitized objective-prism plates can also be applied for the Gaia spectra. At the same time, the plate results confirm the feasibility of observing strong emission lines with Gaia RP/BP.

Astronomical Plate Archives and Binary Blazars Studies

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    There are about 3 million astronomical photographic plates around the globe, representing an important data source for various aspects of astrophysics. The main advantage is the large time coverage of 100 years or even more. Recent digitization efforts, together with the development of dedicated software, enables for the first time, effective data mining and data analyses by powerful computers with these archives. Examples of blazars proposed and/or investigated on the astronomical plates are presented and discussed.

Czech Contribution to Athena

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Maršíková, V., Inemann, A., Skulinová, M., Míka, M.
  • Publikace: Acta Polytechnica. 2011, 51(6), 28-33. ISSN 1210-2709.
  • Rok: 2011
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We describe the recent status of the Czech contribution to the ESA Athena space mission, with emphasis on the development of new technologies and test samples of X-ray mirrors with precise surfaces, based on new materials, and their applications in space. In addition, alternative X-ray optical arrangements are investigated, such as Kirkpatrick-Baez systems.

Czech Participation in INTEGRAL: 1996-2011

  • Autoři: prof. RNDr. René Hudec, CSc., Blažek, M., Hudcová, Věra
  • Publikace: Acta Polytechnica. 2011, 51(6), 20-27. ISSN 1210-2709.
  • Rok: 2011
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The European Space Agency ESA INTEGRAL satellite launched in October 2002 is the first astrophysical satellite of the European Space Agency (ESA) with Czech participation. The results of the first 8 years of investigations of various scientific targets are briefly presented and discussed here, with emphasis on cataclysmic variables and blazars with the ESA INTEGRAL satellite with Czech participation.

Czech Participation in International X-Ray Observatory (IXO)

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Maršíková, V., Inneman, A., Skulinová, M., Míka, M.
  • Publikace: Acta Polytechnica. 2011, 51(2), 46-51. ISSN 1210-2709.
  • Rok: 2011
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Here we describe the recent status of Czech participation in the IXO (International X-ray Observatory) space mission, with emphasis on the development of new technologies and test samples of X-ray mirrors with precise surfaces, based on new materials, and their applications in space. In addition, alternative X-ray optical arrangements are investigated, such as Kirkpatrick-Baez systems.

Czech Participation in the INTEGRAL Satellite: A Review

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ESA INTEGRAL satellite, launched in October 2002, is the first astrophysical satellite of the European Space Agency ESA with Czech participation. The results of the first 7 years of investigations of various scientific targets e.g. cataclysmic variables, blazars, X-ray sources, and GRBs with the ESA INTEGRAL satellite with Czech participation are briefly presented and discussed.

Extremely Lightweight X-Ray Optics Based on Thin Substrates

  • Autoři: prof. RNDr. René Hudec, CSc., Sik, J., Lorenc, M., Pína, L., Marsikova, V., Mika, M., Inneman, A., Skulinova, M.
  • Publikace: EUV AND X-RAY OPTICS: SYNERGY BETWEEN LABORATORY AND SPACE II. Bellingham (stát Washington): SPIE, 2011. Proceedings of SPIE. ISSN 0277-786X. ISBN 9780819486660.
  • Rok: 2011
  • DOI: 10.1117/12.890516
  • Odkaz: https://doi.org/10.1117/12.890516
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on recent progress with development of astronomical X-ray optics based on bent Si wafers. Recent efforts with Si wafers have been focused on new forming technologies such as method of deposition of thin layers. The role of substrates quality in performance of final mirror arrays, as required by large future space X-ray astronomy experiments was also studied.

Full-aperture X-ray tests of Kirkpatrick-Baez modules: preliminary results

  • Autoři: Pína, L., Marsikova, V., prof. RNDr. René Hudec, CSc., Inneman, A., Marsik, J., Cash, W., Shipley, A., Zeiger, B.
  • Publikace: EUV AND X-RAY OPTICS: SYNERGY BETWEEN LABORATORY AND SPACE II. Bellingham (stát Washington): SPIE, 2011. Proceedings of SPIE. ISSN 0277-786X. ISBN 9780819486660.
  • Rok: 2011
  • DOI: 10.1117/12.890517
  • Odkaz: https://doi.org/10.1117/12.890517
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on preliminary results of full aperture X-ray optical tests at the X-ray test facility at the University of Colorado (USA) of four test modules of Kirkpatrick-Baez (KB) X-ray optical systems performed in August 2010. Direct experimental comparisons were made between gold-coated optics of two novel substrates: glass foils and silicon wafers. The preliminary results are promising, with full-width half-maxima of full stacks being of order of 30 arcsec in 2D full arrangement. These results justify further efforts to improve KB optics for use in low-cost, high-performance space-borne astronomical imaging instruments for X-ray wavelengths.

Indirect detections and analyses of GRBs by ionospheric response: Toward a SID-monitor network

  • Autoři: Slosiar, R., prof. RNDr. René Hudec, CSc., Kocka, M., Marko, R., Zatko, M.
  • Publikace: Gamma Ray Bursts 2010. New York: AIP Conference Proceedings, 2011. pp. 393-396. ISSN 0094-243X. ISBN 978-0-7354-0916-3.
  • Rok: 2011
  • DOI: 10.1063/1.3621812
  • Odkaz: https://doi.org/10.1063/1.3621812
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the continued effort for an indirect detection of GRBs by their ionospheric response (SID-Sudden Ionospheric Disturbance) observed at VLF (Very Low Frequency), and discus its possible impact on GRB science and investigations in general. Although few such detections have been already reported in the past, the capability of such alternative and indirect investigations of GRBs still remains to be investigated in more details. We present and discuss examples of detections of GRBs. A network of SID monitors has been created and is operated to detect more GRBs more realiably.

INTEGRAL observations of the GeV blazar PKS 1502+106 and the hard X-ray bright Seyfert galaxy Mkn 841

  • Autoři: Pian, E., Ubertini, P., Bazzano, A., Beckmann, V., Eckert, D., Ghisellini, G., Pursimo, T., Tagliaferri, G., Tavecchio, F., Turler, M., Bianchi, S., Bianchin, V., prof. RNDr. René Hudec, CSc., Maraschi, L., Raiteri, C. M., Soldi, S., Treves, A., Villata, M.
  • Publikace: Astronomy & Astrophysics. 2011, 526 ISSN 0004-6361.
  • Rok: 2011
  • DOI: 10.1051/0004-6361/201015414
  • Odkaz: https://doi.org/10.1051/0004-6361/201015414
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Context. Extragalactic nuclear activity is most effectively explored with observations at high energies, where the most extreme flux and spectral variations are expected to occur, because of changes in either the accretion flow or the kinematics of the plasma. In active galactic nuclei of blazar type, these variations are the most dramatic. Methods. The advent of the Fermi satellite has allowed the start of a systematic and intensive monitoring program of blazars. Blazar outbursts are very effectively detected by the LAT instrument in the MeV-GeV domain, and these can be promptly followed up with other facilities. Based on a Fermi LAT detection of a high MeV-GeV state, we observed the blazar PKS 1502+106 with the INTEGRAL satellite between 9 and 11 August 2008. Simultaneous Swift observations were also accomplished, as well as optical follow-up at the Nordic Optical Telescope.

Kirkpatrick-Baez X-ray Optics: A Review

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: EUV AND X-RAY OPTICS: SYNERGY BETWEEN LABORATORY AND SPACE II. Bellingham (stát Washington): SPIE, 2011. Proceedings of SPIE. ISSN 0277-786X. ISBN 9780819486660.
  • Rok: 2011
  • DOI: 10.1117/12.888268
  • Odkaz: https://doi.org/10.1117/12.888268
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper gives a review and focuses on future possible applications of Kirkpatrick-Baez grazing incidence X-ray optical systems in space and astronomy, we also discuss in detail applications in other areas of science, where (in contrary to astronomy) these systems already have demonstrated their performance and advantages.

Lobster eye optics for nano-satellite X-ray monitor

  • Autoři: Tichý, V., Barbera, M., Collura, A., doc. Ing. Martin Hromčík, Ph.D., prof. RNDr. René Hudec, CSc., Inneman, A., Maršík, J., Maršíkova, V., Pína, L., Šimon, V., Varisco, S.
  • Publikace: EUV AND X-RAY OPTICS: SYNERGY BETWEEN LABORATORY AND SPACE II. Bellingham (stát Washington): SPIE, 2011. Proceedings of SPIE. ISSN 0277-786X. ISBN 9780819486660.
  • Rok: 2011
  • DOI: 10.1117/12.886809
  • Odkaz: https://doi.org/10.1117/12.886809
  • Pracoviště: Katedra řídicí techniky, Katedra radioelektroniky
  • Anotace:
    The Lobster eye design for a grazing incidence X-ray optics provides wide field of view of the order of many degrees, for this reason it would be a convenient approach for the construction of space X-ray monitors. In this paper, we compare previously reported measurements of prototype lobster eye X-ray optics called P-25 with computer simulations and discuss differences between the theoretical end experimentally obtained results. Usability of this prototype lobster eye and manufacturing technology for the nano-satellite mission is assessed. The specific scientific goals are proposed.

Low Cost Optical All Sky Monitoring Camera: Further Developments and Tests

  • DOI: 10.1063/1.3621808
  • Odkaz: https://doi.org/10.1063/1.3621808
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the further development and tests of an low-cost optical all-sky monitor recently tested at the Karlovy Vary Observatory. The recent instrumentation is simple based on a Sigma 8 mm f3.5 EX DG fish-eye lens and CANON 1000D digital CMOS camera. It is a low-cost device suitable for easy replication and still able to detect brighter optical transients simultaneously to GRB triggers. Such OTs have been observed for some of the GRBs such as GRB990123, GRB060117, or recently GRB0803 indicating that some fraction of GRBs can generate optical transient emission accessible by simple small aperture instrumentation as described here. These efforts are accompanied by development of dedicated programmes to access and to evaluate all-sky images, these efforts will be also briefly described.

Multi-Functional Star Tracker - Future Perspectives

  • Pracoviště: Katedra radioelektroniky, Katedra měření
  • Anotace:
    The paper is focused on a multi-functional wide-field star tracker (WFST) idea description and the description of the current state-of-the-art in this field. The idea comes from the proposal handed in to ESA at the beginning of 2011. Star trackers (STs) usually have more than one object-lens with small Field-of-View. They provide very precise information about the attitude in space according to consecutive evaluation of star positions. Our idea of WFST will combine functions of several instruments together, such those as ST, horizon sensor, and all-sky photometry camera. WFST will use fish-eye lens. In the present technology there is not any similar product on market. Nowadays, spacecrafts have to carry more instruments for mentioned applications, which increases weight and thus decreases weight intended for a payload.

Novel Algorithms for Astronomical Plate Analyses

  • Autoři: prof. RNDr. René Hudec, CSc., Hudec, L.
  • Publikace: Journal of Astrophysics and Astronomy. 2011, 32(1-2), 121-123. ISSN 0250-6335.
  • Rok: 2011
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Powerful computers and dedicated software allow effective data mining and scientific analyses in astronomical plate archives. We give and discuss examples of newly developed algorithms for astronomical plate analyses, e.g., searches for optical transients, as well as for major spectral and brightness changes.

Proceedings of SPIE - The International Society for Optical Engineering: Introduction

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L.
  • Publikace: EUV and X-Ray Optics: Synergy Between Laboratory and Space II. Baltimore: SPIE, 2011. Proceedings of SPIE - The International Society for Optical Engineering: Introduction. vol. 8076.
  • Rok: 2011
  • DOI: 10.1117/12.901322
  • Odkaz: https://doi.org/10.1117/12.901322
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This PDF file contains the front matter associated with SPIE Proceedings Volume 8076, including the Title Page, Copyright information, Table of Contents, Introduction, and the Conference Committee listing. © 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Testing the Black Hole No-hair Theorem with OJ287

  • Autoři: Valtonen, M. J., Mikkola, S., Lehto, H. J., Gopakumar, A., prof. RNDr. René Hudec, CSc., Poledniková, J.
  • Publikace: Astrophysical Journal. 2011, 742(1), ISSN 0004-637X.
  • Rok: 2011
  • DOI: 10.1088/0004-637X/742/1/22
  • Odkaz: https://doi.org/10.1088/0004-637X/742/1/22
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We examine the ability to test the black hole no-hair theorem at the 10% level in this decade using the binary black hole in OJ287. In the test we constrain the value of the dimensionless parameter q that relates the scaled quadrupole moment and spin of the primary black hole: q 2 = -q χ2. At the present we can say that q = 1 +- 0.3 (1σ), in agreement with general relativity and the no-hair theorems. We demonstrate that this result can be improved if more observational data are found in historical plate archives for the 1959 and 1971 outbursts. We also show that the predicted 2015 and 2019 outbursts will be crucial in improving the accuracy of the test. Space-based photometry is required in 2019 July due the proximity of OJ287 to the Sun at the time of the outburst. The best situation would be to carry out the photometry far from the Earth, from quite a different vantage point, in order to avoid the influence of the nearby Sun.

Tests of Lobster Eye Optics for Small Space X-ray Telescope

  • Autoři: Tichý, V., Barbera, M., Collura, A., doc. Ing. Martin Hromčík, Ph.D., prof. RNDr. René Hudec, CSc., Inneman, A., Jakůbek, J., Maršík, J., Maršíková, V., Pína, L., Varisco, S.
  • Publikace: Nuclear Instruments and Methods in Physics Research, Section A, Accelerators, Spectrometers, Detectors and Associated Equipment. 2011, 633(1), S169-S171. ISSN 0168-9002.
  • Rok: 2011
  • DOI: 10.1016/j.nima.2010.06.157
  • Odkaz: https://doi.org/10.1016/j.nima.2010.06.157
  • Pracoviště: Katedra řídicí techniky, Katedra radioelektroniky
  • Anotace:
    The Lobster eye design for a grazing incidence X-ray optics provides wide field of view of the order of many degrees, for this reason it can be a convenient approach for the construnction of space all-sky X-ray monitors. We present preliminary results of tests of prototype lobster eye X-ray optics in quasi parallel beam full imaging mode conducted using the 35 meters long X-ray beam-line of INAF-OAPA in Palermo (Italy). X-ray images at the focal plane have been taken with a MCP detector at several energy values from 0.3 keV to 8 keV. The gain, the field of view and the angular resolution have been measured and compared with theoretical values.

Tests of simulated Gaia BP/RP spectra with LDS (Low Dispersion Spectroscopy) photographic sky surveys

  • DOI: 10.1088/1742-6596/328/1/012018
  • Odkaz: https://doi.org/10.1088/1742-6596/328/1/012018
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The LDS (Low Dispersion Spectroscopy) performed in various extended sky surveys with optical telescopes using objective prism and photographic plates offers an interesting opportunity to test simulated low-dispersion spectra for the Gaia BP/RP photometers and to compare them with real data, especially for objects with strong emission lines. We present a review of astrophysics with LDS performed in the past, as well as an overview of existing extended sky surveys (with photographic plates) providing LDS data. Some of them provide almost complete coverage of the northern or southern hemisphere (e.g. the Northern and Southern Mt Wilson - Michigan H alpha surveys or the German La Paz Bolivia Southern Spectral Sky Survey). We show examples of these data and discuss a comparison of existing LDS plate data with expected/simulated Gaia BP/RP data. We show examples of real data for objects with very strong and wide emission features confirming that such features will be detectable with Gaia BP/RP. We also discuss the importance of Gaia RP/BP low-dispersion spectroscopy for astrophysical studies.

The feasibility of independent observations/detections of GRBs in X-rays

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Marsikova, V., Inneman, A.
  • Publikace: Gamma Ray Bursts 2010. New York: AIP Conference Proceedings, 2011. p. 2-855. 1358. vol. 423.
  • Rok: 2011
  • DOI: 10.1063/1.3621819
  • Odkaz: https://doi.org/10.1063/1.3621819
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    According to the observational statistics a large majority of all GRBs exhibit X-ray emission. In addition, a dedicated separate group of GRB, the XRFs, exists which emission dominates in the X-ray spectral range. And the third group of GRB related objects (yet hypothetical) are the group of off-axis observed GRBs (orphan afterglows). These facts justify the consideration of an independent experiment for monitoring, detection and analyses of GRBs and others fast X-ray transients in X-rays. We will present and discuss such experiment based on wide-field X-ray telescopes of Lobster Eye type. The wide field and fine sensitivity of Lobster Eye X-ray All-Sky Monitor make such instruments important tools in study of GRBs and related objects. © 2011 American Institute of Physics.

The Optical Transient Search in the Bamberg Plate Archive

  • Autoři: prof. RNDr. René Hudec, CSc., Kopel, F., Krapp, P., Heber, U., Caye, W.
  • Publikace: Gamma Ray Bursts 2010. New York: AIP Conference Proceedings, 2011. pp. 381-384. ISSN 0094-243X. ISBN 978-0-7354-0916-3.
  • Rok: 2011
  • DOI: 10.1063/1.3621809
  • Odkaz: https://doi.org/10.1063/1.3621809
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    A substantial fraction of gamma-ray bursts is related to objects emitting temporarily optical light, i.e. optical afterglows and optical transients. So far, these phenomena (optical transients) were detected only after related gamma-ray satellite detection. However, taking into account their optical magnitudes at maximum light, these objects should be detectable in various historical and recent optical surveys, including photographic sky patrol. Here we report on an extended study based on blink-comparison of 5004 Bamberg Observatory Southern Sky Patrol Plates performed within a student project (Jugend Forscht).

The Possibility of GRB Investigations by ESA Satellite Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., Hudec, L.
  • Publikace: Gamma Ray Bursts 2010. New York: AIP Conference Proceedings, 2011. pp. 415-418. ISSN 0094-243X. ISBN 978-0-7354-0916-3.
  • Rok: 2011
  • DOI: 10.1063/1.3621817
  • Odkaz: https://doi.org/10.1063/1.3621817
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We refer on further studies on possibility to investigate the Optical Afterglows and Optical Transients of GRBs by the ESA satellite Gaia to be launched in 2012, The satellite will focus on highly precise astrometry of stars and all objects down to limiting magnitude 20. Albeit focusing on astrometry related matters, the satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics. Within the Gaia Variability Unit CU7 and related work package Specific Object Studies there has been a sub-work package accepted for optical counterparts to celestial high-energy sources, a category which includes the optical counterparts (i.e. optical transients and optical afterglows, including counterparts of XRFs and yet hypothetical orphan afterglows) of GRBs. Although the sampling of photometric data will not be optimal for this type of work, the strength of Gaia in such analyses is the fine spectral resolution (spectro-photometry) which will allow the correct classification of related triggers. The possibilities to detect and to analyze optical transients and optical afterglows of GRBs by Gaia will be presented and discussed.

The Puzzle of V407 Cygni

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss the nature and recent observations (optical and gamma-rays) of symbiotics binary/Mira variable V407 Cygni. In addition we discuss another object of similar category, namely the variable star FY Aql with possible association with an eruptive gamma-ray source.

Ultra Low-Dispersion Spectroscopy with Gaia and Photographic Objective Prism Surveys

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    This paper discusses the ultra low-dispersion spectroscopy to be applied in the ESA Gaia space observatory and the ground-based objective-prism plate surveys. Although the dispersion in plate surveys is usually larger than in the Gaia BP/RP spectrometers, the spectral resolutions differ by a factor of 2-3 only, since the resolution in ground-based spectra is seeing-limited. We argue that some of the algorithms developed for digitized objective-prism plates can also be applied for the Gaia spectra. At the same time, the plate results confirm the feasibility of observing strong emission lines with Gaia RP/BP.

Analyses of High-Energy Sources with ESA Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudcová, V.
  • Publikace: X-Ray Astronomy 2009; Present Status, Multi-wavelength Approach and Future Perspectives: Proceedings of the International Conference. Melville, New York: American Institute of Physics, 2010. pp. 583-584. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0795-4.
  • Rok: 2010
  • DOI: 10.1063/1.3475345
  • Odkaz: https://doi.org/10.1063/1.3475345
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ESA satellite Gaia will focus on precise astrometry of objects down to limiting magnitude 20. The satellite will also provide photometric and spectral information which can be used in various astrophysical fields including high-energy astrophysics. Although the sampling of photometric data will not be optimal for this type of work, the strength of Gaia in such analyses is the fine spectral resolution (spectro-photometry) which will allow the correct classification e.g. of GRB-related triggers.

Black Holes in Active Galactic Nuclei

  • Autoři: Valtonen, M. J., Mikkola, S., Merritt, D., Gopakumar, A., Lehto, H. J., Hyvönen, T., Rampadarath, H., Saunders, R., Basta, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Relativity in Fundamental Astronomy (IAU S261): Dynamics, Reference Frames, and Data Analysis (Proceedings of the International Astronomical Union Symposia and Colloquia). Cambridge: Cambridge University Press, 2010. pp. 260-268. ISSN 1743-9213. ISBN 978-0-521-76481-0.
  • Rok: 2010
  • DOI: 10.1017/S1743921309990482
  • Odkaz: https://doi.org/10.1017/S1743921309990482
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Supermassive black holes are common in centers of galaxies. Among the active galaxies, quasars are the most extreme, and their black hole masses range as high as to 61010M. Binary black holes are of special interest but so far OJ287 is the only confirmed case with known orbital elements. In OJ287, the binary nature is confirmed by periodic radiation pulses. The period is twelve years with two pulses per period. The last four pulses have been correctly predicted with the accuracy of few weeks, the latest in 2007 with the accuracy of one day. This accuracy is high enough that one may test the higher order terms in the Post Newtonian approximation to General Relativity.

Detection of GRBs and OTs by All-Sky Optical and SID Monitors

  • DOI: 10.1155/2010/428943
  • Odkaz: https://doi.org/10.1155/2010/428943
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on two alternative simple methods to detect counterparts of cosmic gamma-ray bursts (GRBs) and optical transients (OTs). We report on the development and tests of an alternative optical all-sky monitor recently tested at the Karlovy Vary Observatory. The monitor is based on a Peleng 8 mm fish-eye lens (1 : 3,5-1 : 16) and CANON EOS 350D digital CCD camera. This type of monitor represents a low-cost device suitable for easy replication and still able to detect brighter optical transients simultaneously to GRB triggers. Such OTs have been observed for some of the GRBs such as GRB990123, GRB060117, or recently GRB080319 indicating that some fraction of GRBs can generate optical transient emission accessible by simple small aperture instrumentation as described here.

Four Years of Real-Time GRB Followup by BOOTES-1B (2005-2008)

  • DOI: 10.1155/2010/432172
  • Odkaz: https://doi.org/10.1155/2010/432172
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Four years of BOOTES-1B GRB follow-up history are summarised for the first time in the form of a table. The successfully followed events are described case by case. Further, the data are used to show the GRB trigger rate in Spain on a per-year basis, resulting in an estimate of 18 triggers and about 51 hours of telescope time per year for real-time triggers. These numbers grow to about 22 triggers and 77 hours per year if we include also the GRBs observable within 2 hours after the trigger.

Identification and Analyses in Optical Light of Gamma-Ray Sources with Astronomical Archival Plates

  • DOI: 10.1155/2010/618975
  • Odkaz: https://doi.org/10.1155/2010/618975
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Paper deals with efforts related to investigation of astronomical archival plates with modern methods i.e. analyses of image recorded on plates by dedictaed programs and powerful computers.

Identification and Investigation of High Energy Sources on Astronomical Archival Plates

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V.
  • Publikace: X-Ray Astronomy 2009; Present Status, Multi-wavelength Approach and Future Perspectives: Proceedings of the International Conference. Melville, New York: American Institute of Physics, 2010. pp. 161-162. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0795-4.
  • Rok: 2010
  • DOI: 10.1063/1.3475182
  • Odkaz: https://doi.org/10.1063/1.3475182
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Many high-energy sources exhibit variable optical emission which can be analysed over prolonged time intervals with reasonable sampling by means af astronomical archival plates. Few selected examples are shown and discussed.

Indirect detections and analyses of GRBs by ionospheric response

  • Autoři: prof. RNDr. René Hudec, CSc., Slošiar, R.
  • Publikace: X-Ray Astronomy 2009; Present Status, Multi-wavelength Approach and Future Perspectives: Proceedings of the International Conference. Melville, New York: American Institute of Physics, 2010. pp. 59-60. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0795-4.
  • Rok: 2010
  • DOI: 10.1063/1.3475352
  • Odkaz: https://doi.org/10.1063/1.3475352
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss the independent and indirect detection of GRBs by their ionospheric response (SID - Sudden Ionospheric Disturbance) observed at VLF (Very Low Frequency), and evaluate its possible impact on GRB science and investigations in general. Although few such detections have been already reported in the past, the capability of such alternative and indirect investigations of GRBs still remains to be investigated in more details. We present and discuss examples of such VLF/SID detection of GRBs 060124A, GRB080319D a GRB080320A. A network of SID monitors has been created and is operated to detect more GRBs. The importance of these detections for GRB analyses and GRB science in general is still to be further and in full detail exploited.

Investigation of high-energy sources in optical light by ESA Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudec, L., Hudcová, V.
  • Publikace: 8th International Workshop on Multifrequency Behaviour of High Energy Cosmic Sources. Roma: Societa Astronomica Italiana, 2010. pp. 476-481. Memorie della Societa Astronomica Italiana, Supplementi. ISSN 1824-0178.
  • Rok: 2010
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We refer on the project related to the ESA satellite Gaia to be launched in 2012 with focus on the high precision astrometry of stars and all objects down to limiting magnitude 20. The satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics.Within the Gaia Variability Unit CU7 and related work package Specific Object Studies, there are sub-work packages accepted for optical counterparts of celestial high-energy sources and cataclysmic variables. Although the sampling of the photometric data will not be optimal for this type of work, the strength of Gaia in such analyses is the fine spectral resolution (spectro-photometry and ultra-low dispersion spectroscopy) which will allow the correct classication of related triggers.

Kirkpatrick-Baez (KB) and Lobster Eye (LE) Optics for Astronomical and Laboratory Applications

  • DOI: 10.1155/2010/139148
  • Odkaz: https://doi.org/10.1155/2010/139148
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Most of grazing incidence (reflective) X-ray imaging systems used in astronomy and in other (laboratory) applications are based on the Wolter 1 (or modified) arrangement. But there were proposed also other designs and configurations, which are considered for future applications for both in laboratory and (finitely) in space. The Kirkpatrick-Baez (KB) lenses as well as various types of Lobster-Eye (LE) optics and MCP/Micropore optics serve as an example. Analogously to Wolter lenses, the X-rays are mostly reflected twice in these systems to create focal images. The KB systems have already found wide usage in laboratory and synchrotron, both application are reviewed and discussed in detail in this paper. While this paper focuses on future possible applications of non-Wolter grazing incidence systems in space and astronomy, we also discuss in detail applications in other areas of science, where (in contrary to astronomy) some of these systems have demonstrated their advantages.

Lessons learned from ESA INTEGRAL: cataclysmic variables and blazars

  • Autoři: prof. RNDr. René Hudec, CSc., Gális, R., Kocka, M.
  • Publikace: 8th International Workshop on Multifrequency Behaviour of High Energy Cosmic Sources. Roma: Societa Astronomica Italiana, 2010. pp. 220-225. Memorie della Societa Astronomica Italiana, Supplementi. ISSN 1824-0178.
  • Rok: 2010
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The results of investigations of cataclysmic variables and blazars with the ESA INTEGRAL satellite are briefly presented and discussed. It is evident that the satellite serves as an efficient tool to study some of these objects, e.g. cataclysmic variables containing a magnetic white dwarf and blazars in outbursts.

Lobster-Eye X-Ray Astronomy

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Marsikova, V., Inneman, A.
  • Publikace: X-Ray Astronomy 2009; Present Status, Multi-wavelength Approach and Future Perspectives: Proceedings of the International Conference. Melville, New York: American Institute of Physics, 2010. pp. 585-586. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0795-4.
  • Rok: 2010
  • DOI: 10.1063/1.3475346
  • Odkaz: https://doi.org/10.1063/1.3475346
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on technical and astrophysical aspects of Lobster-Eye wide-field X-ray telescopes expected to monitor the sky with high sensitivity and angular resolution of order of 1 arcmin. They will contribute essentially to study of various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. (C) 2010 American Institute of Physics.

Measuring Black Hole Spin in OJ287

  • Autoři: Valtonen, M. J., Mikkola, S., Lehto, H. J., Hyvonen, T., Nilsson, K., Merritt, D., Gopakumar, A., Rampadarath, H., prof. RNDr. René Hudec, CSc., Basta, M., Saunders, R.
  • Publikace: Celestial Mechanics and Dynamical Astronomy. 2010, 106(3), 235-243. ISSN 0923-2958.
  • Rok: 2010
  • DOI: 10.1007/s10569-009-9252-z
  • Odkaz: https://doi.org/10.1007/s10569-009-9252-z
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We model the binary black hole system OJ287 as a spinning primary and a non-spinning secondary. It is assumed that the primary has an accretion disk which is impacted by the secondary at specific times. These times are identified as major outbursts in the light curve of OJ287. This identification allows an exact solution of the orbit, with very tight error limits. Nine outbursts from both the historical photographic records as well as from recent photometric measurements have been used as fixed points of the solution: 1913, 1947, 1957, 1973, 1983, 1984, 1995, 2005 and 2007 outbursts. This allows the determination of eight parameters of the orbit. Most interesting of these are the primary mass of 1.84.10(10) M-circle dot, the secondary mass 1.40.10(8) M-circle dot, major axis precession rate 39 degrees.1 per period, and the eccentricity of the orbit 0.70. The dimensionless spin parameter is 0.28 +/- 0.01 (1 sigma).

Measuring the Spin of the Primary Black Hole in OJ287

  • Autoři: Valtonen, M. J., Mikkola, S., Merritt, D., Gopakumar, A., Lehto, H. J., Hyvonen, T., Rampadarath, H., Saunders, R., Basta, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Astrophysical Journal. 2010, 709(2), 725-732. ISSN 0004-637X.
  • Rok: 2010
  • DOI: 10.1088/0004-637X/709/2/725
  • Odkaz: https://doi.org/10.1088/0004-637X/709/2/725
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The compact binary system in OJ287 is modeled to contain a spinning primary black hole with an accretion disk and a non-spinning secondary black hole. Using post-Newtonian (PN) accurate equations that include 2.5PN accurate non-spinning contributions, the leading-order general relativistic and classical spin-orbit terms, the orbit of the binary black hole in OJ287 is calculated and as expected it depends on the spin of the primary black hole. Using the orbital solution, the specific times when the orbit of the secondary crosses the accretion disk of the primary are evaluated such that the record of observed outbursts from 1913 up to 2007 is reproduced. The timings of the outbursts are quite sensitive to the spin value.

New Technologies for Future Space X-ray Telescopes

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Maršiková, V., Inneman, A., Skulinová, M., Mika, M.
  • Publikace: X-Ray Astronomy 2009; Present Status, Multi-wavelength Approach and Future Perspectives: Proceedings of the International Conference. Melville, New York: American Institute of Physics, 2010. pp. 587-588. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0795-4.
  • Rok: 2010
  • DOI: 10.1063/1.3475347
  • Odkaz: https://doi.org/10.1063/1.3475347
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present and discuss progress in glass and Si wafer technologies for future imaging X-ray astronomy missions, as well as properties of test mirrors produced and tested. (C) 2010 American Institute of Physics.

Operating a global network of autonomous observatories

  • Autoři: Kubánek, P., Castro-Tirado, A. J., de Ugarte Postigo, A., Cunniffe, R., Prouza, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Proceedings of SPIE Vol. 7740 - Software and Cyberinfrastructure for Astronomy. Washington: SPIE, 2010. pp. 77400U-00-77400U-12. ISSN 0277-786X. ISBN 978-0-8194-8230-3.
  • Rok: 2010
  • DOI: 10.1117/12.857222
  • Odkaz: https://doi.org/10.1117/12.857222
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss our experiences operating a heterogeneous global network of autonomous observatories. The observatories are presently situated on four continents, with a fifth expected during the summer of 2010. The network nodes are small to intermediate diameter telescopes (<= 150 cm) owned by different institutions but running the same observatory control software. We report on the experience gained during construction, commissioning and operation of the observatories, as well as future plans. Problems encountered in the construction and operation of the nodes are summarised. Operational statistics as well as scientific results from the observatories are also presented.

Photometry and Low Dispersion Spectroscopy with ESA Gaia

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudec, L.
  • Publikace: Advances in Astronomy. 2010, 2010(si2), 1-7. ISSN 1687-7969.
  • Rok: 2010
  • DOI: 10.1155/2010/781421
  • Odkaz: https://doi.org/10.1155/2010/781421
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ESA satellite to be launched in 2012 will focus on highly precise astrometry of stars and all objects down to limiting magnitude 20. Albeit focusing on astrometry related matters, the satellite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics. Within the Gaia Variability Unit CU7 and related work package Specific Object Studies there are subwork packages accepted for optical counterparts of celestial high-energy sources and cataclysmic variables. Although the sampling of the photometric data will not be optimal for this type of work, the strength of Gaia in such analyses is the fine spectral resolution (spectrophotometry and ultra-low dispersion spectroscopy) which will allow the correct classication of related triggers. We will review the available low dispersion spectral surveys and discuss their use for a simulation and tests of the Gaia algorithms and Gaia data.

The Role of Ground-Based Robotic Observatories in Satellite Projects

  • DOI: 10.1155/2010/594854
  • Odkaz: https://doi.org/10.1155/2010/594854
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss the role of robotic telescopes in satellite projects, as well as related strategies. Most satellite projects in space astrophysics focus on high-energy astrophysics from X-rays to gamma-rays. A large fraction of objects of high-energy astrophysics emit also optical light, which is, in many cases, variable. The observation of these sources at optical wavelengths can provide valuable inputs for multispectral analysis of various categories of celestial high-energy (HE) sources. As the magnitudes of numerous objects are bright and can be hence accessed by robotic ground-based observatories, these observations can contribute to investigations and analyses of HE sources. We discuss in detail this possible contribution, with emphasis on the ESA INTEGRAL mission. In addition to this, there are also satellite projects outside the high-energy astronomy, in which the robotic telescopes can also play an important role. We will illustrate this on the example of the ESA satellite Gaia.

V1062 Tau - comparison of the X-Ray (INTEGRAL) and optical (D50) data

  • Autoři: Blažek, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Proceedings of 8th INTEGRAL Workshop "The Restless Gamma-ray Universe". Trieste: SISSA/ISAS, 2010. ISSN 1824-8039.
  • Rok: 2010
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present the multifrequency analysis of the nova-type cataclysmic variable star V1062 Tau based on INTEGRAL / IBIS X-Ray data, robotic telescope D50 optical data and other instruments.

A high resolution x-ray spectrometer utilizing Kirkpatrick-Baez optics and off-plane gratings

  • Autoři: McEntaffer, R. L., prof. RNDr. René Hudec, CSc., Murray, N. J., Holland, A. D.
  • Publikace: EUV and X-Ray Optics: Synergy between Laboratory and Space. Bellingham: SPIE, 2009. pp. 736014-736014-10. SPIE Conference Proceedings. ISSN 0277-786X. ISBN 978-0-8194-7634-0.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present the design of a high resolution X-ray spectrometer for space based X-ray studies. This novel design utilizes a Kirkpatrick-Baez geometry with an off-plane grating as the secondary optic. This design has been proposed to NASA for flight onboard a suborbital rocket. The approach is low cost, low risk and has applications for future orbital missions.

Active x-ray optics

  • Pracoviště: Katedra řídicí techniky, Katedra radioelektroniky
  • Anotace:
    There is a growing need for multiply nested large area X-ray mirrors with very fine angular resolution in future X-ray astrophysics experiments. Despite of promising results of several exploited technologies, it is not demonstrated yet that these technologies will provide the required angular resolutions of order of few arcsec. The alternative approach described in this paper is the method of active X-ray optics. In addition, active approaches based on computer control may be applied directly during manufacturing of advanced X-ray optics elements. We propose these methods as an alternative for the IXO project recently under study by ESA/NASA/JAXA.

Advanced x-ray optics with Si wafers and slumped glass

  • Autoři: prof. RNDr. René Hudec, CSc., Marsikova, V., Mika, M., Sik, J., Lorenc, M., Pína, L., Inneman, A., Skulinova, M.
  • Publikace: Optics for EUV, X-Ray, and Gamma-Ray Astronomy IV. Bellingham: SPIE, 2009. pp. 74370S-74370S-12. Proceedings of SPIE. ISSN 0277-786X. ISBN 978-0-8194-7727-9.
  • Rok: 2009
  • DOI: 10.1117/12.827978
  • Odkaz: https://doi.org/10.1117/12.827978
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the continuation of the development of test samples of astronomical x-ray optics based on thermally formed glass foils and on bent Si wafers. Experiments with thermal glass forming have continued adding wider range of evaluated and optimized parameters including viscosity and internal stress analyses, as well as investigation of mounting influences. Experiments with Si wafers focused on their quality improvements such as flatness and thickness uniformity in order to better meet the requirements of future X-ray astronomy projects applications, as well as on study of their surface quality, defects analysis, and methods for its reproducible measurement.

Alternative methods for detection of GRBs

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on two altenative simple methos to detect counterparts of cosmic gamma-ray bursts (GRBs). We report on the development and tests of an alternative optical all-sky monitor recently tested at the Karlovy Vary Observatory. The monitor is based on a Peleng 8 mm .sh-eye lens (1:3,5-1:16) and CANON EOS 350D digital CCD camera. This type of monitor represents a low-cost device suitable for easy replication and still able to detect brighter optical transients simultaneously to GRB triggers. Such OTs have been observed for some of the GRBs such as GRB990123, GRB060117, or recently GRB0803 indicating that some fraction of GRBs can generate optical transient emission accessible by simple small aperture instrumentation as described here. These efforts are accompanied by development of dedicated programmes to access and to evaluate all-sky images,.. The sekond method is the GRB detection based on thein ionospheric response.

Back-up technologies for IXO

  • Autoři: prof. RNDr. René Hudec, CSc., Sik, J., Lorenc, M., Pína, L., Semencova, V., Mika, M., Inneman, A., Skulinova, M.
  • Publikace: EUV and X-Ray Optics: Synergy between Laboratory and Space. Bellingham: SPIE, 2009. pp. 73600L-73600L-12. SPIE Conference Proceedings. ISSN 0277-786X. ISBN 978-0-8194-7634-0.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on recent progress with development of astronomical X-ray optics based on thermally formed glass foils and on bent Si wafers. Experiments with thermal glass forming have continued adding wider range of evaluated and optimized parameters. Recent efforts with Si wafers have been focused on their quality improvements such as flatness and thickness uniformity in order to better meet the requirements of future X-ray astronomy projects applications, as well as on study of their surface quality, defects analysis, and methods for its reproducible measurement. The role of substrates quality in performance of final mirror arrays, as required by large future space X-ray astronomy experiments was also studied.

Blazars with Integral

  • Autoři: prof. RNDr. René Hudec, CSc., Blažek, M., Kocka, M., Pian, E.
  • Publikace: Baltic Astronomy. 2009, 18(3/4), 327-335. ISSN 1392-0049.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The analysis of the INTEGRAL data for blazars, a specific class of the active galactic nuclei, is described. These objects are promising objects for observations by INTEGRAL, especially during their active states. A strategy for their future investigation is proposed and discussed.

Czech Participation in Ixo

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Maršíková, V., Inneman, A., Skulinová, M., Mika, M.
  • Publikace: Baltic Astronomy. 2009, 18(3/4), 345-352. ISSN 1392-0049.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The future space X-ray astronomy imaging missions require very large collecting areas at fine angular resolution and reasonable weight. The new substrates for X-ray mirrors such as silicon wafers and thin thermally formed glass enable wide applications of precise and very light weight (volume densities 2.3 to 2.5 g cm-3) optics. Here we describe the recent status of the Czech participation in the IXO space mission with emphasis on the development of new technologies and test samples of X-ray mirrors with precise surfaces, based on new materials, and their applications in space.

ESA Gaia: The variability based on low dispersion spectra

  • Autoři: prof. RNDr. René Hudec, CSc., Šimon, V., Hudec, L., Kocka, M.
  • Publikace: Proceedings of the 40th Conference on Variable Stars Research. Brno: BRNO, 2009. pp. 17-27. ISSN 1801-5964.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The ESA satellite in development Gaia to be launched in 2011 will focus on highly precise astrometry of stars and all objects down to limiting magnitude 20. Albeit focusing on astrometry related matters, the satelite will also provide photometric and spectral information and hence important inputs for various branches of astrophysics. Within the Gaia Variability Unit CU7 and related work package Specific Object Studies there has been a sub-work package accepted for optical counterparts to celestial high-energy sources, a category which includes the optical counterparts (i.e. optical transients and optical afterglows, including counterparts of XRFs and yet hypothetical orphan afterglows) of GRBs, and also microquasars.

Faint objects on INTEGRAL/IBIS mosaics in 15 - 80 keV energy range

  • Autoři: Blažek, M., prof. RNDr. René Hudec, CSc.,
  • Publikace: Proceedings of "The Extreme sky: Sampling the Universe above 10 keV". Trieste: SISSA/ISAS, 2009. Proceedings of Science (PoS). ISSN 1824-8039.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We discuss searches for positive detection of selected candidates (i.e. faint objects, mostly intermediate polars and blazars) in INTEGRAL IBIS data. We discuss various approaches with emphasis on detection and confirmation of faint objects with low signal to noise ratio.

History of grazing incidence x-ray optics in the Czech Republic

  • Autoři: prof. RNDr. René Hudec, CSc.,
  • Publikace: EUV and X-Ray Optics: Synergy between Laboratory and Space. Bellingham: SPIE, 2009. pp. 73600D-73600D-15. SPIE Conference Proceedings. ISSN 0277-786X. ISBN 978-0-8194-7634-0.
  • Rok: 2009
  • DOI: 10.1117/12.820356
  • Odkaz: https://doi.org/10.1117/12.820356
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The X-ray optics is a key element of various X-ray telescopes, X-ray microscopes, as well as other X-ray imaging instruments. The grazing incidence X-ray lenses represent the important class of X-ray optics. The replication technology represents an important alternative to other methods of X-ray optics production. We report on the past (first replicated Xray mirror has been produced by our group almost 40 years ago), present and future of replication of X-ray optics with emphasis on grazing incidence optics of various types and geometry. The various types of X-ray optics produced by replication with emphasis on astronomical optics are described and summarized. It is shown that the replicated X-ray optics is expected to still play a major role in future space experiments and projects such as the ESA/NASA/JAXA IXO project and other coming space missions.

Indirect detections and analyses of GRBs by ionospheric response

  • Autoři: Slosiar, R., prof. RNDr. René Hudec, CSc.,
  • Publikace: Gamma-Ray Burst: Sixth Huntsville Symposium. Austin: American Institute of Physic, 2009. pp. 428-430. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0670-4.
  • Rok: 2009
  • DOI: 10.1063/1.3155941
  • Odkaz: https://doi.org/10.1063/1.3155941
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the independent and indirect detection of GRBs by their ionospheric response (SID-Sudden Ionospheric Disturbance) observed at VLF (Very Low Frequency), and discus its possible impact on GRB science and investigations in general. Although few such detections have been already reported in the past, the capability of such alternative and indirect investigations of GRBs still remains to be investigated in more details. We present and discuss examples of such VLF/SID detection of GRBs 060124A, GRB080319D a GRB080320A. A network of SID monitors has been created and is operated to detect more GRBs. The importance of these detections for GRB analyses and GRB science in general is still to be further and in full detail exploited. Some possible outcomes in this direction will be outlined and discussed.

Low-Cost Optical All-Sky Monitor For Detection of Bright OTs of GRBs

  • Autoři: prof. RNDr. René Hudec, CSc., Spurny, M., Krizek, P., prof. Mgr. Petr Páta, Ph.D., Řeřábek, M.
  • Publikace: Gamma-Ray Burst: Sixth Huntsville Symposium. Austin: American Institute of Physic, 2009. pp. 215-217. AIP Conference Proceedings. ISSN 0094-243X. ISBN 978-0-7354-0670-4.
  • Rok: 2009
  • DOI: 10.1063/1.3155881
  • Odkaz: https://doi.org/10.1063/1.3155881
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the development and tests of an alternative optical all-sky monitor recently tested at the Karlovy Vary Observatory. The monitor is based on a Peleng 8 mm fish-eye lens (1:3, 5-1:16) and CANON EOS 350D digital CCD camera. This type of monitor represents a low-cost device suitable for easy replication and still able to detect brighter optical transients simultaneously to GRB triggers. Such OTs have been observed for some of the GRBs such as GRB990123, GRB060117, or recently GRB0803 indicating that some fraction of GRBs can generate optical transient emission accessible by simple small aperture instrumentation as described here. These efforts are accompanied by development of dedicated programmes to access and to evaluate all-sky images, these efforts will be also briefly described. The processing and measuring of image data is complicated and sophisticated deconvolution algorithms are used for image restoration.

Low-Dispersion Spectroscopy: a Comparison of the GAIA and Objective-Prism Surveys

  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The extremely low-dispersion spectroscopy to be implemented in the Gaia space observatory is compared with the ground-based objective-prism plate surveys. Although the dispersion in plate surveys usually is larger than in the Gaia BP/RP spectrometers, the spectral resolutions differ by a factor of 2--3 only, since the resolution of ground-based spectra is seeing-limited. This allows to consider that some of the algorithms developed for digitized objective-prism plates can be also applied for the Gaia spectra.

PROCEEDINGS OF THE INTEGRAL/BART WORKSHOP 2009

  • Autoři: prof. RNDr. René Hudec, CSc., Ripa, J., Kocka, M., Havlíková, R.
  • Publikace: Baltic Astronomy. 2009, 18(3/4), 265-270. ISSN 1392-0049.
  • Rok: 2009

Replicated grazing incidence micromirrors

  • Autoři: prof. RNDr. René Hudec, CSc., Pína, L., Inneman, A., Semencova, V., Švéda, L.
  • Publikace: EUV and X-Ray Optics: Synergy between Laboratory and Space. Bellingham: SPIE, 2009. pp. 73600G-73600G-12. SPIE Conference Proceedings. ISSN 0277-786X. ISBN 978-0-8194-7634-0.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    The replication technology originally developed for astronomical X-ray optics can be also effectively applied for laboratory mirrors with small apertures, even below few mm. Grazing incidence micromirrors of ellipsoidal or parabolic shape with apertures below 1 mm have numerous potential applications in many areas of applied physics, molecular biology and material research, including synchrotron. One of the most important applications of such optics is in its combination with microfocus X-ray generator. Extremely intense collimated or focused high-quality X-ray beams from tabletop equipment can be obtained in this way. It is shown that though developed primarily for macromolecular crystallography, this combination gave excellent results also in other fields of science and technology. Computer raytracing and experimental data characterizing mirror and X-ray beam parameters in typical applications are also presented.

Small X-Ray Telescope Based on Lobster Eye X-Ray Optics and Pixel Detector

  • Autoři: Tichý, V., doc. Ing. Martin Hromčík, Ph.D., prof. RNDr. René Hudec, CSc., Inneman, A., Jakůbek, J., Maršík, J., Pína, L., Semencová, V., Švéda, L.
  • Publikace: EUV and X-Ray Optics: Synergy between Laboratory and Space. Bellingham: SPIE, 2009. pp. 736011-736011-7. SPIE Conference Proceedings. ISSN 0277-786X. ISBN 978-0-8194-7634-0.
  • Rok: 2009
  • DOI: 10.1117/12.820729
  • Odkaz: https://doi.org/10.1117/12.820729
  • Pracoviště: Katedra řídicí techniky, Katedra radioelektroniky
  • Anotace:
    Two experimental modules of small X-ray telescopes based on the Lobster eye X-ray optics are presented. These modules are regarded to use for x-ray astronomy applications in space. At this time, the optical tests of these modules have been performed. Results of these tests are presented.

Tests of Imaging with Lobster-Eye X-Ray Optics and MEDIPIX2 Detector

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    The results of preliminary experiments with the Medipix2 detector and the lobster-eye optics are presented and discussed. Tests are performed with X-rays having a photon energy of about 8 keV. The field of view and the spatial resolution are determined. The dependence of the image distortion and the intensity on the source position is investigated.

Tests of Lobster-Eye Optics for a Small X-Ray Telescope

  • Pracoviště: Katedra řídicí techniky, Katedra radioelektroniky
  • Anotace:
    Two experimental lobster-eye specimens, called P25 and P90, are described. These lobster eyes are built in simple modules, their length does not exceed 1 m and a future version can be held on a small satellite. The results of tests of these modules in visible light are presented.

The strange optically variable source SWIFT J195509+261406 and implication for optical observers

  • Autoři: prof. RNDr. René Hudec, CSc., Šinon, V., Castro-Tirado, A. J.
  • Publikace: Proceedings of the 40th Conference on Variable Stars Research. Brno: BRNO, 2009. p. 45-52. ISSN 1801-5964.
  • Rok: 2009
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We observed a normal GRB and found a peculiar galactic source (b = -1.0) with intense flaring activity. Optical flares of over 4 magnitudes and durations of ~1 min (not observed in "classical SGRs", not only a "high Galactic extinction" problem).This confirms the important role of automated robotic telescopes and cameras. The object represent an yet unknown representation of optical variability, different from all galactic variable objects observed before.

Alternative Solution for an Low-Cost Optical All-Sky Monitor

  • Autoři: prof. RNDr. René Hudec, CSc., Spurny, M., Krizek, M., Zicha, J., Nekola, M.
  • Publikace: 39. Conference On Variable Stars. Brno: BRNO, 2008. p. 3-9. ISSN 1801-5964.
  • Rok: 2008
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We report on the development and tests of an alternative optical all-sky monitor recently tested at the Karlovy Vary Observatory. The monitor is based on a Peleng 8 mm fish-eye lens (1:3,5-1:16) and CANON EOS 350D digital CCD camera. This type of monitor represents a low-cost device suitable for easy replication and still able to detect brighter optical transients simultaneously to GRB triggers. Such OTs have been observed in the past for some of the GRBs such as GRB990123 or GRB060117 indicating that some fraction of GRBs can generate optical transient emission accessible by simple small aperture instrumentation as described here.

ESA Gaia and Variable Objects

  • Autoři: prof. RNDr. René Hudec, CSc., Simon, V., Hudec, L.
  • Publikace: 39. Conference On Variable Stars. Brno: BRNO, 2008. p. 29-34. ISSN 1801-5964.
  • Rok: 2008
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Albeit focusing on astrometry, the ESA Gaia space mission will also provide spectrophotometry for all objects down to mag 20 over 5 years operation period. Typically 50 to 200 measurements per object including variable stars, cataclysmic variables and optical counterparts of celestial high-energy sources can be expected during this time interval. Also optical counterparts of celestial high-energy sources, including afterglows and optical transients of GRBs can be detected and investigated this way.

Zobrazovací vlastnosti rentgenové optiky račí oko - srovnání teorie a experimentu

  • Pracoviště: Katedra řídicí techniky
  • Anotace:
    Širokoúhlá rentgenová optika typu račí oko je vhodným kandidátem na optický systém pro celoblohový monitor (All Sky Monitor) v oboru rentgenové astronomie. Pro korektní funkci systému je však třeba vzít v úvahu řadu vad této optiky. V tomto příspěvku se zabýváme srovnáním prvních systematických experimentů, které se této problematiky týkají, s jejich počítačovou simulací. Konkrétně popisujeme dva případy. Jednak se jedná o systematický posun polohy zdroje vůči ideální poloze, který je způsoben principem fungování optiky, a který dosahuje teoreticky až 0.8 mm (RMS). A dále se jedná o změnu detekovaného spektra zdroje způsobenou reflektivitou optiky závislou na energii fotonů.

A photometric redshift of z = 6.39 +/- 0.12 for GRB 050904

  • Autoři: Haislip, J. B., Nysewander, M. C., Reichart, D. E., Levan, A., Tanvir, N., Cenko, S. B., Fox, D. B., Price, P. A., Castro-Tirado, A. J., Gorosabel, J., Evans, C. R., Figueredo, E., MacLeod, C. L., Kirschbrown, J. R., Jelinek, M., Guziy, S., Postigo, A. D., Cypriano, E. S., LaCluyze, A., Graham, J., Priddey, R., Chapman, R., Rhoads, J., Fruchter, A. S., Lamb, D. Q., Kouveliotou, C., Wijers, R. A. M. J, Bayliss, M. B., Schmidt, B. P., Soderberg, A. M., Kulkarni, S. R., Harrison, F. A., Moon, D. S., Gal-Yam, A., Kasliwal, M. M., prof. RNDr. René Hudec, CSc. doc. Ing. Stanislav Vítek, Ph.D. Kubanek, P., Crain, J. A., Foster, A. C., Clemens, J. C., Bartelme, J. W., Canterna, R., Hartmann, D. H., Henden, A. A., Klose, S., Park, H. S., Williams, G. G., Rol, E., O'Brien, P., Bersier, D., Prada, F., Pizarro, S., Maturana, D., Ugarte, P., Alvarez, A., Fernandez, A. J. M., Jarvis, M. J., Moles, M., Alfaro, E., Ivarsen, K. M., Kumar, N. D., Mack, C. E., Zdarowicz, C. M., Gehrels, N., Barthelmy, S., Burrows, D. N.
  • Publikace: Nature. 2006, 440(7081), 181-183. ISSN 0028-0836.
  • Rok: 2006
  • DOI: 10.1038/nature04552
  • Odkaz: https://doi.org/10.1038/nature04552
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Gamma-ray bursts (GRBs) and their afterglows are the most brilliant transient events in the Universe. Both the bursts themselves and their afterglows have been predicted to be visible out to redshifts of z approximate to 20, and therefore to be powerful probes of the early Universe(1,2). The burst GRB 000131, at z = 4.50, was hitherto the most distant such event identified(3). Here we report the discovery of the bright near-infrared afterglow of GRB 050904 (ref. 4). From our measurements of the near-infrared afterglow, and our failure to detect the optical afterglow, we determine the photometric redshift of the burst to be z = 6.39(-0.12)(+0.11) (refs 5-7). Subsequently, it was measured(8) spectroscopically to be z = 6.29 +/- 0.01, in agreement with our photometric estimate. These results demonstrate that GRBs can be used to trace the star formation, metallicity, and reionization histories of the early Universe.

BOOTES-IR: a robotic nIR astronomical observatory devoted to follow-up of transient phenomena

  • DOI: 10.1117/12.671579
  • Odkaz: https://doi.org/10.1117/12.671579
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    "BOOTES-IR" is the extension of the BOOTES experiment, which has been operating in Southern Spain since 1998, to the near-infrared (nIR). The goal is to follow up the early stage of the gamma ray burst (GRB) afterglow emission in the nIR, as BOOTES does already at optical wavelengths. The scientific case that drives the BOOTES-IR performance is the study of GRBs with the support of spacecraft like HETE-2, INTEGRAL and SWIFT (and GLAST in the future). Given that the afterglow emission in both, the nIR and the optical, in the instances immediately following a GRB, is extremely bright (reached V = 8.9 in one case), it should be possible to detect this prompt emission at nIR wavelengths too. Combined observations by BOOTES-IR and BOOTES-1 and BOOTES-2 since 2006 can allow for real time identification of trustworthy candidates to have a ultra-high redshift (z > 6). It is expected that, few minutes after a GRB, the nIR magnitudes be H ~ 10-15, hence very high quality spectra can be obtained for objects as far as z = 10 by much larger ground-based telescopes. A significant fraction of observing time will be available for other scientific projects of interest, objects relatively bright and variable, like Solar System objects, brown dwarfs, variable stars, planetary nebulae, compact objects in binary systems and blazars.

GRB follow-up with BOOTES optical chapter 5: The Swift era

  • Autoři: Jelínek, M., Castro-Tirado, A. J., Kubánek, P., doc. Ing. Stanislav Vítek, Ph.D., Postigo, A.d.U., prof. RNDr. René Hudec, CSc.,
  • Publikace: Gamma-Ray Bursts in the Swift Era. Melville, New York: American Institute of Physics, 2006. p. 688-691. AIP CONFERENCE PROCEEDINGS. vol. 836. ISSN 0094-243X. ISBN 0-7354-0326-0.
  • Rok: 2006
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    BOOTES is a robotic system, whose primary aim is to observe gamma-ray burst prompt emission. Since 1998 BOOTES has provided follow-up observations for more than 70 GRBs; the most important results obtained so far are the detection of an OT in the short/hard GRB 000313 error box, the detection of several optical after-glow for long/soft GRBs and the non-detection of optical emission simultaneous to the high energy emission for several GRBs (both long/soft and short/hard events). During the time of operation we have got triggers from CGRO/BATSE, BeppoSAX, HETE-2, INTEGRAL and Swift. Here we present our early detections of GRB optical emission using the 30 cm Bootes-1B telescope in the R.V and I-bands since the launch of Swift.

Statistical analysis of RHESSI GRB databases

  • Autoři: Ripa, J., prof. RNDr. René Hudec, CSc., Meszaros, A., Hajdas, W., Wigger, C.
  • Publikace: Il Nuovo Cimento B. 2006, 121(12), 1493-1494. ISSN 1594-9982.
  • Rok: 2006

The bright optical flash from GRB 060117

  • DOI: 10.1051/0004-6361:20065092
  • Odkaz: https://doi.org/10.1051/0004-6361:20065092
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present a discovery and observation of an extraordinarily bright prompt optical emission of the GRB060117 obtained by a wide-field camera atop the robotic telescope FRAM of the Pierre Auger Observatory from 2 to 10 min after the GRB. We found rapid average temporal flux decay of alpha = -1.7 +/- 0.1 and a peak brightness R = 10.1 mag. Later observations by other instruments set a strong limit on the optical and radio transient fluxes, unveiling an unexpectedly rapid further decay. We present an interpretation featuring a relatively steep electron-distribution parameter p similar or equal to 3.0 and providing a straightforward solution for the overall fast decay of this optical transient as a transition between reverse and forward shock.

GRB 050509b: the elusive optical/nIR/mm afterglow of a short-duration GRB

  • Autoři: Castro-Tirado, A. J., de Ugarte Postigo, A., Gorosabel, J., Fathkullin, T., Sokolov, V., Bremer, M., Márquez, I., Marín, A. J., Guziy, S., Jelínek, M., Kubánek, P., prof. RNDr. René Hudec, CSc., doc. Ing. Stanislav Vítek, Ph.D., Mateo Sanguino, T. J., Eigenbrod, A., Pérez-Ramírez, M. D., Sota, A., Masegosa, J., Prada, F., Moles, M.
  • Publikace: Astronomy & Astrophysics. 2005, 439(2), L15-L18. ISSN 0004-6361.
  • Rok: 2005
  • DOI: 10.1051/0004-6361:200500147
  • Odkaz: https://doi.org/10.1051/0004-6361:200500147
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    We present multiwavelength observations of a short duration gamma-ray burst detected by Swift ( GRB 050509b) collected between 0 seconds and similar to 18.8 days after the event. No optical, near infrared or millimetre emission has been detected in spite of the well localised X-ray afterglow, confirming the elusiveness of the short duration events. We also discuss the possibility of the burst being located in a cluster of galaxies at z = 0. 225 or beyond. In the former case, the spectral energy distribution of the neighbouring, potential host galaxy, favours a system harbouring an evolved dominant stellar population ( age similar to 360 Myr), unlike most long duration GRB host galaxies observed so far, i.e. thus giving support to a compact binary merger origin. Any underlying supernova that could be associated with this particular event should have been at least 3 magnitudes fainter than the type Ib/c SN 1998bw and 2.3 mag fainter than a typical type Ia SN.

Simultaneous and optical follow-up GRB observations by BOOTES

  • DOI: 10.1393/ncc/i2005-10137-x
  • Odkaz: https://doi.org/10.1393/ncc/i2005-10137-x
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    Since 1998 BOOTES has provided follow-up observations for more than 70 GRBs; the most important results obtained so far are the detection of an OT in the GRB 000313 error box and the non-detection of optical emission simultaneous to the high-energy emission for several GRBs (both long/soft and short/hard events).

BOOTES: Technological developments and scientific results by a stereoscopic system with two stations spaced by 240 km

  • DOI: 10.1063/1.1810953
  • Odkaz: https://doi.org/10.1063/1.1810953
  • Pracoviště: Katedra radioelektroniky
  • Anotace:
    An overview of the technological developments at the Burst Observer and Optical Transient Exploring System (BOOTES) is given. The most important scientific results obtained so far are the detection of an OT in the GRB 000313 error box and the non detection of optical emission simultaneous for GRB 010220, GRB 030226 (long/soft events), GRB 020531 and GRB 021201 (short/hard events). With the recent instrumental and technical developments, BOOTIES multiplies its science capabilities.

Effect of BOOTES Image Data Compression using Karhunen-Loeve Decomposition upon Astrometry Measurement Accuracy

GRB 030115, simultaneous observations by BOOTES-1

GRB 030226 simultaneous optical observations

Optical Transient Monitor (OTM) for BOOTES Project

Recent Developments in the BOOTES Experiment

  • Autoři: de Ugarte Postigo, A., Mateo Sanguino, T.J., Castro Cerón, J.M., prof. Mgr. Petr Páta, Ph.D., Ing. Martin Bernas, CSc., Jelínek, M., prof. RNDr. René Hudec, CSc., McBreen, S., Berná, J.Á., García Dabó, C.E., Gorosabel, J., Más-Hesse, J.M., Soria, T., de la Morena, B.A., Torres Riera, J., Castro-Tirado, A.J.
  • Publikace: AIP Conference Proceedings 662. Cambridge: Massachusetts Institute of Technology, 2003. pp. 553-555. ISBN 0-7354-0122-5.
  • Rok: 2003

Two versions of Optical Transient Monitor Software for BOOTES Experiment

Detection of an optical transient following the 13 March 2000 short/hard gamma-ray burst

GRB 020531, simultaneous optical observations

Application of the Karhunen-Loeve Decomposition for Astronomical Data Storage

BOOTES-1: a Robotic Telescope 1.998 - 2.000

  • Autoři: Castro Cerón, J.M., Castro-Tirado, A., Soldán, J., prof. RNDr. René Hudec, CSc., Ing. Martin Bernas, CSc., prof. Mgr. Petr Páta, Ph.D., Mateo Sanguino, T., de Ugarte Postigo, A., Berná, Á., Nekola, M., Gorosabel, J., de la Morena, B., Más-Hesse, J.M., Giménez, Á., Torres Riera, J.
  • Publikace: COSMICS EXPLOSIONS: Gamma-Ray Bursts & Related Phenomena. Jerusalem: The Hebrew University of Jerusalem, 2001.
  • Rok: 2001

Gamma Ray Burst Follow Up Observations with BOOTES-1 in 1998-2000

GRB 010220, Simultaneous Optical Observations by BOOTES-1

New Properties of Optical Transient Monitor (OTM)

New Version of Optical Transient Monitor for BOOTES Project

Search for Gamma Ray Bursts Quasi Simultaneous Optical Emission with BOOTES-1

Two Years of Gamma-Ray Burst Follow-Up Observations with BOOTES-1

Application of the Karhunen-Loeve Decomposition for Astronomical Data Storage

Gamma-Ray Burst Follow-Up Observations with BOOTES-1 in 1998-2000

GRB 000126, Optical Observations

GRB 000313, Optical Transient in the BATSE Error Box

GRB 000607, Optical Observations

Novel Image Data Compression Method Suitable for Satellite Applications

Two Years of Gamma-Ray Burst Follow-Up Observations with BOOTES-1

The Burst Observer and Optical Transient Exploring System (BOOTES)

Za stránku zodpovídá: Ing. Mgr. Radovan Suk