Analysis of NuSTAR and Suzaku observations of Cyg X-1 in the hard state: evidence for a truncated disc geometry
@article{Basak2017AnalysisON, title={Analysis of NuSTAR and Suzaku observations of Cyg X-1 in the hard state: evidence for a truncated disc geometry}, author={Rupal Basak and Andrzej A. Zdziarski and Michael L. Parker and Nazma Islam}, journal={Monthly Notices of the Royal Astronomical Society}, year={2017}, volume={472}, pages={4220-4232} }
The geometry of the accretion flow in black hole X-ray binaries in the hard state, in particular the position of the disc inner edge, has been a subject of intense debate in recent years. We address this issue by performing a spectral study of simultaneous observations of Cyg X-1 in the hard state by NuSTAR and Suzaku. The same data were analysed before, and modelled by a lamppost containing hybrid electrons and located very close to the horizon, whose emission was incident on a surrounding…
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References
SHOWING 1-10 OF 93 REFERENCES
NuSTAR AND SUZAKU OBSERVATIONS OF THE HARD STATE IN CYGNUS X-1: LOCATING THE INNER ACCRETION DISK
- Physics
- 2015
We present simultaneous Nuclear Spectroscopic Telescope Array (NuSTAR ) and Suzaku observations of the X-ray binary Cygnus X-1 in the hard state. This is the first time this state has been observed…
Spectral analysis of the XMM–Newton data of GX 339–4 in the low/hard state: disc truncation and reflection
- Physics
- 2016
We analyse all available observations of GX 339--4 by XMM-Newton in the hard spectral state. We jointly fit the spectral data by Comptonization and the currently best reflection code, relxill. We…
THE SOFT STATE OF CYGNUS X-1 OBSERVED WITH NuSTAR: A VARIABLE CORONA AND A STABLE INNER DISK
- Physics
- 2016
We present a multi-epoch hard X-ray analysis of Cygnus X-1 in its soft state based on four observations with the Nuclear Spectroscopic Telescope Array (NuSTAR). Despite the basic similarity of the…
The reflection component from Cygnus X-1 in the soft state measured by Nustar and Suzaku
- Physics
- 2013
The black hole binary Cygnus X-1 was observed in late 2012 with the Nuclear Spectroscopic Telescope Array (NuSTAR) and Suzaku, providing spectral coverage over the ∼1–300 keV range. The source was in…
Suzaku Results on Cygnus X-1 in the Low/Hard State
- Physics
- 2008
AbstractThe black-hole binary Cygnus X-1 was observed for 17 ks with the Suzaku X-ray observatory in 2005October, while it was in a low/hard state with a 0.7–300 keV luminosity of 4.6×10 37 erg s −1…
Probing the Inner Region of Cygnus X-1 in the Low/Hard State through Its X-Ray Broadband Spectrum
- Physics
- 2001
We present the broadband X-ray spectrum of Cyg X-1 in the low/hard state as observed by the instruments on board BeppoSAX. The spectrum spans from 0.1 to 200 keV, allowing the total accretion…
The soft component and the iron line as signatures of the disc inner radius in Galactic black hole binaries
- Physics
- 2014
The inner radius of the accretion disc around a black hole in the low/hard state can be measured in one of two ways. First, via the extent of broadening of the iron emission line, and secondly, from…
Radiation mechanisms and geometry of cygnus X-1 in the soft state
- Physics
- 1999
We present X-ray/γ-ray spectra of Cyg X-1 observed during the transition from the hard to the soft state and in the soft state by ASCA, RXTE and CGRO/OSSE in 1996 May and June. The spectra consist of…
A Long, Hard Look at the Low/Hard State in Accreting Black Holes
- Physics
- 2006
We present the first results of coordinated multiwavelength observations of the Galactic black hole GX 339-4 in a canonical low/hard state, obtained during its 2004 outburst. XMM-Newton observed the…
X-ray irradiation in XTE J1817−330 and the inner radius of the truncated disc in the hard state
- Physics
- 2008
The key aspect of the very successful truncated disc model for the low/hard X-ray spectral state in black hole binaries is that the geometrically thin disc recedes from the last stable orbit at the…