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Related papers: On accretion flow in Soft X-ray Transients

200 papers

We show that the X-ray outburst light curves of four transient anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), namely XTE J1810-197, SGR 0501+4516, SGR 1627-41 and CXOU J164710.2-455216, can be produced by the fallback…

High Energy Astrophysical Phenomena · Physics 2012-10-08 Sirin Caliskan , Unal Ertan

The microquasar GX 339-4 experienced a new outburst in 2010: it was observed simultaneously at various wavelengths from radio up to soft gamma-rays. We focused on observations that are quasi-simultaneous with those made with the INTEGRAL…

High Energy Astrophysical Phenomena · Physics 2015-05-30 M. Cadolle Bel , J. Rodriguez , P. D'Avanzo , D. M. Russell , J. Tomsick , S. Corbel , F. Lewis , F. Rahoui , M. Buxton , P. Goldoni , E. Kuulkers

We have analyzed {\it Rossi} X-ray timing explorer (RXTE) pointed observations of the outbursts of black hole and neutron star soft X-ray transients in which an initial low/hard state or `island' state, followed by a transition to a softer…

Astrophysics · Physics 2009-11-10 Wenfei Yu , Michiel van der Klis , Rob Fender

Recent observations of two black hole candidates (GX 339-4 and J1753.5-0127) in the low-hard state (L_X/L_Edd ~ 0.003-0.05) suggest the presence of a cool accretion disk very close to the innermost stable orbit of the black hole. This runs…

Astrophysics · Physics 2009-11-13 Caroline D'Angelo , Dimitrios Giannios , Cornelis Dullemond , Henk Spruit

The soft excess seen in many AGN is most probably due to partially ionized material moving at relativistic speeds close to the black hole. There are currently two potential geometries for this material, one where it is out of the line of…

Astrophysics · Physics 2008-11-26 Chris Done , Sergei Nayakshin

Soft X-ray transients are a subclass of the low mass X-ray binaries that occasionally show a sudden rise in their soft X-ray luminosity; otherwise, they remain in an extremely faint state. We investigate the accretion properties of the soft…

High Energy Astrophysical Phenomena · Physics 2024-07-29 Debjit Chatterjee , Arghajit Jana , Hsiang-Kuang Chang

We probe models of disc truncation in the hard spectral state of an outburst of the well-known X-ray transient GX 339--4. We test a large number of different models of disc reflection and its relativistic broadening, using two independent…

High Energy Astrophysical Phenomena · Physics 2019-03-20 Marta A. Dziełak , Andrzej A. Zdziarski , Michał Szanecki , Barbara De Marco , Andrzej Niedźwiecki , Alex Markowitz

[abridged] We model the X-ray reprocessing from a strong co-rotating flare above an accretion disk in active galactic nuclei. We explore the horizontal structure and evolution of the underlying hot spot. To obtain the spectral evolution…

Astrophysics · Physics 2009-11-13 R. W. Goosmann , M. Mouchet , B. Czerny , M. Dovciak , V. Karas , A. Rozanska , A. -M. Dumont

We select a sample of nearby Ultraluminous X-ray sources with long XMM-Newton observations and analyse all the available XMM-Newton data using both X-ray spectral fitting techniques and hardness-intensity diagrams. The sample includes IC…

High Energy Astrophysical Phenomena · Physics 2014-03-05 Fabio Pintore , Luca Zampieri , Anna Wolter , Tomaso Belloni

A widely accepted picture of an accretion flow in the luminous soft spectral state of X-ray binary systems is a geometrically thin disc structure much like the classic analytic solution of Shakura \& Sunyaev. Although the analytic models…

In this work, which is a continuation of Castell\'o-Mor et al. (2016), we present new X-ray and infrared (IR) data for a sample of active galactic nuclei (AGN) covering a wide range in Eddington ratio over a small luminosity range. In…

Astrophysics of Galaxies · Physics 2017-02-01 Núria Castelló-Mor , Shai Kaspi , Hagai Netzer , Pu Du , Chen Hu , Luis C. Ho , Jin-Ming Bai , Wei-Hao Bian , Ye-Fei Yuan , Jian-Min Wang

Accreting black holes show a complex and diverse behaviour in their soft spectral states. Although these spectra are dominated by a soft, thermal component which almost certainly arises from an accretion disc, there is also a hard X-ray…

Astrophysics · Physics 2016-01-13 P. T. Zycki , C. Done , D. A. Smith

We present the results of a detailed analysis of RXTE observations which show an unusual state transition between high-soft and low-soft states in the microquasar GRS 1915+105. The RXTE pointed observations reveal that these events appeared…

Astrophysics · Physics 2007-05-23 S. Naik , A. R. Rao , Sandip K. Chakrabarti

We report some remarkable and unexpected results of optical/UV/X-ray follow-up observations of bright soft X-ray selected AGN from the ROSAT All-Sky-Survey. The majority of these AGN are rather anonymous Seyfert galaxies, mostly of the…

Astrophysics · Physics 2007-05-23 K. Mannheim , D. Grupe , K. Beuermann , H. -C. Thomas , H. H. Fink

We present a self-consistent model of accretion flows which unifies four distinct spectral states observed in black hole X-ray binaries: quiescent, low, intermediate and high states. In the quiescent, low and intermediate states, the flow…

Astrophysics · Physics 2009-10-30 A. A. Esin , J. E. McClintock , R. Narayan

We have investigated the long-term evolution of individual anomalous X-ray pulsars (AXPs) and soft gamma repeaters (SGRs) with relatively well constrained X-ray luminosity and rotational properties. In the frame of the fallback disc model,…

High Energy Astrophysical Phenomena · Physics 2016-01-29 Onur Benli , Unal Ertan

Over the last few years X-ray observations of broad-line radio galaxies (BLRGs) by ASCA, RXTE and BeppoSAX have shown that these objects seem to exhibit weaker X-ray reflection features (such as the iron K\alpha line) than radio-quiet…

Astrophysics · Physics 2009-11-07 D. R. Ballantyne , R. R. Ross , A. C. Fabian

Analytical investigation of time-dependent accretion in disks is carried out. We consider a time-dependent disk in a binary system at outburst which has a fixed tidally-truncated outer radius. The standard Shakura-Sunyaev model of the disk…

Astrophysics · Physics 2011-05-23 G. V. Lipunova , N. I. Shakura

(abridged) The accretion disk in AGN is expected to produce strong outflows, in particular a UV-line driven wind. Despite providing a good fit to the data, current spectral models of the X-ray spectrum of AGN observed through an accretion…

Astrophysics · Physics 2009-11-13 N. J. Schurch , C. Done

Highlights from the RXTE All Sky Monitor (ASM) during 1996 and 1997 are reviewed with particular attention to X-ray transients. The ASM has detected 117 sources. These include 12 recurrent transients and 10 new X-ray sources, some of which…

Astrophysics · Physics 2009-09-25 R. A. Remillard