A5031560664- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- High-pressure geophysics and materials
- Particle Detector Development and Performance
- Mechanics and Biomechanics Studies
- Scientific Measurement and Uncertainty Evaluation
- Particle Accelerators and Free-Electron Lasers
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Geophysics and Gravity Measurements
- X-ray Spectroscopy and Fluorescence Analysis
- Superconducting Materials and Applications
- Advanced X-ray Imaging Techniques
- Galaxies: Formation, Evolution, Phenomena
- Dark Matter and Cosmic Phenomena
- Nuclear Physics and Applications
- History and Developments in Astronomy
- Atomic and Molecular Physics
- Medical Imaging Techniques and Applications
University of Warsaw
2024
Tata Institute of Fundamental Research
2024
European Space Research and Technology Centre
2003-2017
Nagoya University
2010-2016
Tokyo Metropolitan University
2016
European Space Astronomy Centre
2007-2014
European Space Agency
2010-2011
Ehime University
2010
Engineering Science Analysis (United States)
2001-2009
Middle East Technical University
2009
High-sensitivity wide-band X-ray spectroscopy is the key feature of Suzaku observatory, launched on 2005 July 10. This paper summarizes spacecraft, in-orbit performance, operations, and data processing that are related to observations. The scientific instruments, high-throughput telescopes, CCD cameras, non-imaging hard detector also described.
The payload of the Italian/Dutch spacecraft BeppoSAX includes a set four X-ray concentrators each geometric area together with imaging gas scintillation proportional counter detectors located at focal planes. One these detectors, Low-Energy Concentrator Spectrometer (LECS), is sensitive to X-rays in energy range 0.1-10 keV, while other three cover narrower 1.3-10 keV. In order achieve extended low-energy response LECS novel type has been developed which dispenses separate drift and regions...
view Abstract Citations (272) References (73) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The X-Ray Spectral Properties of Accretion Disks in Binaries White, N. E. ; Stella, L. Parmar, A. Using EXOSAT observations, the spectral properties persistent emission from a number X-ray burst sources, high-luminosity low-mass binaries (LMXRB), and galactic black hole candidates are compared with various models for an accretion disk surrounding compact object...
view Abstract Citations (229) References (40) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Discovery of 3.8 Hour Periodic Intensity Dips and Eclipses from the Transient Low-Mass X-Ray Binary EXO 0748-676 Parmar, A. N. ; White, E. Giommi, P. Gottwald, M. Using EXOSAT Observatory authors have discovered a new transient X-ray burst source that shows 8.3 minute duration eclipses recur with period 3.82 hr. If companion star is on main sequence, eclipse...
Aims. We study the spectrum of cosmic X-ray background (CXB) in energy range ~5-100 keV.
Context.During the first year in operation, INTEGRAL, European Space Agency's γ-ray observatory, has detected more than 28 new bright sources galactic plane which emit bulk of their emission above 10 keV.
We report the possible detection (99.3% of statistical significance) redshifted Fe iron line emission in X-ray afterglow Gamma-ray burst GRB970508 observed by BeppoSAX. Its energy is consistent with redshift putative host galaxy determined from optical spectroscopy. The disappeared about 1 day after burst. have also analyzed spectral variability during outburst event that characterizes this GRB. spectrum gets harder flare, turning to steep when flux decreases. variability, intensity and...
MAXI J1659-152 is a bright X-ray transient black-hole candidate binary system discovered in September 2010. We report here on MAXI, RXTE, Swift, and XMM-Newton observations during its 2010/2011 outburst. find that the first one half week of outburst light curves display drops intensity at regular intervals, which we interpret as absorption dips. About three weeks into outbursts, again are seen. These dips have, however, spectral behaviour opposite to dips, related fast state changes (hence...
We present BeppoSAX follow-up observations of GRB 980425 obtained with the Narrow Field Instruments (NFI) in 1998 April, May, and November. The first NFI observation has detected within 8' radius error box gamma-ray burst (GRB) an X-ray source positionally consistent supernova 1998bw, which exploded a day 980425, fainter source, not position supernova. former is following pointings exhibits decline factor 2 six months. If it associated SN this detection emission from Type I above keV. latter...
We report results of a BeppoSAX (0.1-200 keV) observation the Z-type low-mass X-ray binary GX 17+2. The source was on so-called horizontal and normal branches. Energy spectra were selected based position in hardness-intensity diagram. continuum could be fairly well described by sum ~0.6 keV blackbody, contributing ~10% observed 0.1-200 flux, Comptonized component, resulting from upscattering ~1 seed photons an electron cloud with temperature ~3 optical depth ~10. Iron K line edge also...
X-ray observations have revealed that many microquasars and low-mass binaries (LMXBs) exhibit narrow absorption features identified with resonant from other abundant ions. In well studied systems there is evidence for blue-shifts, indicating outflowing plasmas. We succesfully model the changes in both continuum Fe during dips all bright dipping LMXBs observed by XMM-Newton (EXO 0748-676, XB 1254-690, X 1624-490, MXB 1659-298, 4U 1746-371 1916-053) as resulting primarily an increase column...
The recurrent hard pulsating X-ray transient X0115+63 was observed with BeppoSAX on 1999 March 19, when the source at a 2-10 keV flux level of ~310 mcrab. We report high-energy spectrum source, concentrating cyclotron resonant scattering features. is strongly pulse phase dependent, and absorption features are detected virtually all phases. In particular, four absorption-like 12.74, 24.16, 35.74, 49.5 in descending edge main peak profile. ratios between centroid energies lines respect to...
view Abstract Citations (139) References (54) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Transient 42 Second X-Ray Pulsar EXO 2030+375. I. Discovery and the Luminosity Dependence of Pulse Period Variations Parmar, A. N. ; White, E. Stella, L. Izzo, C. Ferri, P. discovery a new transient X-ray pulsar, 2030+375, that is associated with Be star companion, reported. results series EXOSAT observations, where evolution pulsar's properties over two orders...
view Abstract Citations (117) References (26) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Transient 42 Second X-Ray Pulsar EXO 2030+375. II. Luminosity Dependence of the Pulse Profile Parmar, A. N. ; White, E. Stella, L. During an outburst from transient, s, X-ray pulsar 2030+375, marked luminosity-dependent changes in profile were observed. At high luminosities pulse consisted a smooth asymmetric main separated by about 180 deg phase small...
view Abstract Citations (83) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Discovery of 0.2 HZ Quasi-periodic Oscillations in the X-Ray Flux Transient 42 Second Pulsar EXO 2030+374 Angelini, L. ; Stella, Parmar, A. N. discovery about Hz quasi-periodic oscillations (QPOs) 1-15 keV X-ray flux transient s pulsar 2030 + 375 is reported. detection QPOs power spectra this was made possible by application a newly developed technique to decouple...
We report on the 0.5-200 keV spectral properties of Cyg X-1 observed at different epochs with Narrow Field Instruments BeppoSAX satellite. The source was in its soft state during first observation 1996 June. In second September, had parameters characteristic to hard state. A X-ray excess, a broad Fe Kα line and Compton reflection are clearly detected both states. soft-state broadband continuum is well modeled by disk blackbody (accounting for excess) upscattering photons hybrid,...
On 1998 May 9–11, BeppoSAX observed the low-luminosity Seyfert 1 galaxy NGC 4051 in an ultra-dim X-ray state. The 2–10 keV flux (1.26 × 10−12 erg cm−2 s−1) was about 20 times fainter than its historical average value, and remained steady along whole observation (∼2.3 d). flat spectrum (Γ ≃ 0.8) intense iron line (EW 600 eV) are best explained by assuming that active nucleus has switched off, leaving only a residual reflection component visible.
INTEGRAL regularly scans the Galactic plane to search for new objects and in particular absorbed sources with bulk of their emission above 10-20 keV.The first source was discovered on 2003 January 29, 0.5 • from further observed X-rays XMM-Newton.This source, IGR J16318-4848, is intrinsically strongly by cold matter displays exceptionally strong fluorescence lines.The likely infrared/optical counterpart indicates that J16318-4848 probably a High Mass X-Ray Binary neutron star or black hole...
view Abstract Citations (115) References (28) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS An EXOSAT Observation of Quiescent and Flare Coronal X-Ray Emission from Algol White, N. E. ; Culhane, J. L. Parmar, A. Kellett, B. Kahn, S. van den Oord, G. H. Kuijpers, X-ray emission the system is believed to originate in a corona associated with K star. The authors have used Observatory make 35 hr continuous observation centered on occultation star by B primary....
We report the detection of narrow and X-ray absorption lines at keV in persistent emission dipping low-mass binary 4U 1323-62 during a 2003 January XMM-Newton observation. These features are superposed on broad feature centered keV. During intervals equivalent width increases while that decreases, consistent with presence less strongly ionized material line-of-sight. As observed previously, changes 1.0–10 spectrum dips inconsistent simple increase by cool material. However, both continuum...
view Abstract Citations (102) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Bursting Behavior of the Transient X-Ray Burst Source EXO 0748-676: A Dependence between Properties and Strength Persistent Emission Gottwald, M. ; Haberl, F. Parmar, A. N. White, E. Between 1985 February 15 July 19 EXOSAT made eight observations transient X-ray source 0748-676. Within this time interval persistent flux varied by a factor 5 from high to low state...
view Abstract Citations (87) References (44) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Intensity and Source State Dependence of the Quasi-periodic Oscillations in Scorpius X-1 van der Klis, M. ; Stella, L. White, N. Jansen, F. Parmar, A. oscillations (QPO) at 6 Hz were discovered from EXOSAT observations Sco its quiescent state by Middleditch Priedhorsky. The authors report here on properties QPO seen earlier X-1. During these also detected when was an...