Related papers: A variable magnetic disc wind in the black hole X-…
We examine stochastic variability in the dynamics of X-ray emission from the black hole system GRS 1915+105, a strongly variable microquasar commonly used for studying relativistic jets and the physics of black hole accretion. The analysis…
We want to test if self-similar magneto-hydrodynamic (MHD) accretion-ejection models can explain the observational results for accretion disk winds in BHBs. In our models, the density at the base of the outflow, from the accretion disk, is…
Theoretical models of accretion discs and observational data indicate that the X-ray emission from the inner parts of an accretion disc can irradiate its outer regions and induce a thermal wind, which carries away the mass and angular…
The presence of blueshifted absorption lines in the X-ray spectra of Black Hole Low Mass X-ray Binaries is the telltale of massive outflows called winds. These signatures are found almost exclusively in soft states of high-inclined systems,…
The X-ray spectrum of GRS 1915+105 is known to have a ``broad iron spectral feature'' in the spectral hard state. Similar spectral features are often observed in Active Galactic Nuclei (AGNs) and other black-hole binaries (BHBs), and…
Stellar-mass black holes with relativistic jets, also known as microquasars, mimic the behavior of quasars and active galactic nuclei. Because timescales around stellar-mass black holes are orders of magnitude smaller than those around more…
We interpret observed features of the black hole candidate GRS1915+105 in the light of the advective flow paradigm. The light curve of this black hole is seen to be of four classes, Soft, Hard, Semi-Soft and Intermediate. Each class can…
We present X-ray observations of the Black-Hole Binary GRS 1915+105 made with the RXTE (Rossi X-ray Timing Explorer). We concentrated on timing analysis of the strong variability focusing on its aperiodic variability on short (<1s) time…
Blueshifted X-ray absorption lines (preferentially from Fe XXV and Fe XXVI present in the 6-8 keV range) indicating the presence of massive hot disk winds in Black Hole (BH) X-ray binaries (XrB) are most generally observed during the soft…
Winds from black hole accretion disks are essential ingredients in understanding the coevolution between the supermassive black hole and its host galaxy. The great difference of dynamical ranges from small-scale accretion disk simulations…
Hercules X-1 is one of the best studied highly magnetised neutron star X-ray binaries with a wealth of archival data. We present the discovery of an ionised wind in its X-ray spectrum when the source is in the high state. The wind detection…
Among the population of known galactic black hole X-ray binaries, GRS 1915+105 stands out in multiple ways. It has been in continuous outburst since 1992, and has shown a wide range of different states that can be distinguished by their…
Powerful ionized accretion disk winds are often observed during episodic outbursts in Galactic black hole transients. Among those X-ray absorbers, \fexxvi\ doublet structure (Ly$\alpha_1$+Ly$\alpha_2$ with $\sim 20$eV apart) has a unique…
To understand the nature of supercritical accretion, we systematically analyze the {\it RXTE}/PCA data of GRS 1915+105 in its quasi-steady states, by choosing data with small variability during 1999 -- 2000. We apply a multicolor disk plus…
Accreting black holes show characteristic 'reflection' features in their X-ray spectra, including the iron K$\alpha$ fluorescence line, which result from X-rays radiated by a compact central corona being reprocessed in the accretion disc…
GRS 1915$+$105 is a stellar-mass black hole that is well known for exhibiting at least 12 distinct classes of X-ray variability and correlated multi-wavelength behavior. Despite such extraordinary variability, GRS 1915$+$105 remained one of…
GRS 1915$+$105 was the stellar-mass black hole that best reproduced key phenomena that are also observed in Type-1 active galactic nuclei. In recent years, however, it has evolved to resemble a Type-2 or Compton-thick AGN. Herein, we report…
We discuss the observational consequences of black hole spin in X-ray binaries within the framework of the standard thin accretion disk model. When compared to theoretical flux distribution from the surface of a thin disk surrounding a Kerr…
Black hole X-ray binary systems (BHBs) contain a close companion star accreting onto a stellar-mass black hole. A typical BHB undergoes transient outbursts during which it exhibits a sequence of long-lived spectral states, each of which is…
The RXTE observations of GRS 1915+105 have given a new impulse to the study of spectral and timing properties of the X-ray emission of black hole candidates. At variance with any other known source, GRS 1915+105 shows dramatic changes on…