Related papers: Spectro-timing study of GX 339-4 in a hard interme…
We present a detailed spectral analysis of Swift and NuSTAR observations of the very faint X-ray transient and black hole system Swift J1357.2-0933 during an early low hard state of its 2017 outburst. Swift J1357.2-0933 was observed at…
GX 339-4 has been one of the key sources for unravelling the accretion ejection coupling in accreting stellar mass black holes. After a long period of quiescence between 1999 and 2002, GX 339-4 underwent a series of 4 outbursts that have…
We report on the results from Suzaku observations of the Galactic black hole X-ray binary H 1743-322 in the low/hard state during its outburst in 2012 October. We appropriately take into account the effects of dust-scattering to accurately…
Variable features in black hole X-ray Binaries (BH-XRBs) are observed in different energy ranges and time scales. The physical origin of different spectral states in BH-XRBs and their relations with the underlying accretion disc are still…
We have performed a joint spectral and timing analysis of the outburst of GRS 1739-278 in 2014 based on Swift and INTEGRAL data. We show that during this outburst the system exhibited both intermediate states: hard and soft. Peaks of…
Black hole accretion flows show rapid X-ray variability. The Power Spectral Density (PSD) of this is typically fit by a phenomenological model of multiple Lorentzians for both the broad band noise and Quasi-Periodic Oscillations (QPOs). Our…
We discuss a series of observations of the black hole candidate GX 339-4 in low luminosity, spectrally hard states. We present spectral analysis of three separate archival Advanced Satellite for Cosmology and Astrophysics (ASCA) data sets…
We present simultaneous XMM-Newton and INTEGRAL observations of the luminous black hole transient and relativistic jet source GX 339-4. GX 339-4 started an outburst on November of 2006 and our observations were undertaken from January to…
We present the spectral and timing study of the bright NS-LMXB GX 5-1 using \textit{\textit{AstroSat}/LAXPC} and \textit{SXT} observations conducted in the year 2018. During the observation, the source traces out the complete HB and NB of…
The X-ray quasi-periodic oscillation (QPO) at $\sim 2.6 \times 10^{-4}$ Hz in RE J1034+396 has been robustly observed in the 0.2-10 keV band of one $\sim 90$ ks XMM-Newton observation, but was not detected in subsequent observations. Here,…
We report the detection of type-B quasi-periodic oscillation (QPO) of the black hole X-ray binary Swift J1728.9-3613 observed by NICER during the 2019 outburst. A type- B QPO was observed for the first two days and it disappeared as flux…
We report the discovery with XMM-Newton of an approximately 7 mHz X-ray (0.3-10.0 keV) quasi-periodic oscillation (QPO) from the eclipsing, high-inclination black hole binary IC 10 X-1. The QPO is significant at > 4.33 sigma confidence…
We present the broadband spectral analysis of all the six hard, intermediate and soft state NuSTAR observations of the recently discovered transient black hole X-ray binary MAXI J1348-630 during its first outburst in 2019. We first model…
We study spectral properties of GX 339-4 during its 2010-11 outburst with Two Component Advective Flow (TCAF) model after its inclusion in XSPEC as a table model. We compare results fitted by TCAF model with combined disk black body and…
We present the results of the timing and color analysis of more than two hundred RXTE/PCA observations of the bright black-hole transient GX 339-4 obtained during its 2002/2003 outburst. The color-intensity evolution of the system, coupled…
We report on the X-ray spectral (using XMM-Newton data) and timing behavior (using XMM-Newton and Rossi X-ray Timing Explorer [RXTE] data) of the very faint X-ray transient and black hole system Swift J1357.2-0933 during its 2011 outburst.…
We report the first detection of evolving Low-Frequency Quasi-periodic Oscillation (LFQPO) frequencies in hard X-rays upto $100$ keV with $AstroSat/LAXPC$ during `unusual' outburst phase of Swift J1727.8-1613 in hard-intermediate state…
We present a detailed timing and spectral study of an extremely variable narrow-line Seyfert~1 galaxy NGC 4748 using observations in the year 2017 and 2014 performed with AstroSat and XMM-Newton, respectively. Both observations show…
We report the few hundred second anti-correlated soft lags between soft and hard energy bands in the source GX 339-4 using RXTE observations. In one observation, anti-correlated soft lags were observed using the ISGRI/INTEGRAL hard energy…
(abridged) In this paper we extend the idea suggested previously by Petri (2005a,b) that the high frequency quasi-periodic oscillations observed in low-mass X-ray binaries may be explained as a resonant oscillation of the accretion disk…