12 papers
X-Ray Timing Properties of the Black Hole Candidate IGR J17091-3624 During the 2022 Outburst Onset with AstroSat
Sree Bhattacherjee, Biplob Sarkar
We present the evolution of rapid X-ray timing variability in the black hole X-ray binary IGR J17091-3624 during the initial phase of its 2022 outburst using a ~3-day-long AstroSat…
The Polarized X-ray Universe: Insights and Discoveries
Arbind Pradhan, Sree Bhattacherjee, Biplob Sarkar
Polarization is one of the fundamental natures of electromagnetic radiation. The detection of polarization or polarized photons from distant X-ray radiating systems (such as X-ray…
Multifaceted Accretion: The Interplay of Turbulence, Resistivity, Thermal Transport, and Dust around Black Holes
Asish Jyoti Boruah, Liza Devi, Biplob Sarkar
Accretion near black holes (BHs) is multidimensional, with turbulence, resistivity, thermal transport, and dust dynamics all playing essential roles. In cold accretion discs (ADs)…
An Overview of the Effect of Self-Gravity on the Structure of Accretion Discs
Darashan Saikia, Liza Devi, Biplob Sarkar +1
In astrophysical systems like X-ray binaries (XRBs), active galactic nuclei (AGN), and young stellar objects (YSOs), we often observe a very fundamental structure called accretion…
An Overview of Rossby Wave Instability in Accretion Discs surrounding Black Holes
Bibhuti Bhusan Dutta, Liza Devi, Biplob Sarkar +1
The Rossby Wave Instability (RWI) has become an important concept in understanding the hydrodynamics (HDs) of accretion discs (ADs), especially in systems around black holes (BHs)…
Probing the energy-dependent temporal nature of MAXI J1803-298 with AstroSat and NICER
Arbind Pradhan, Akash Garg, Ranjeev Misra +1
We performed the spectral and temporal analysis of MAXI J1803-298 using AstroSat/LAXPC and NICER observations taken in May 2021 during the initial phase of the outburst. We found t…
Energy-dependent temporal study of GX 13+1 with AstroSat observation
Arbind Pradhan, Sree Bhattacherjee, Biplob Sarkar
In this work, we performed an energy-dependent study of low-frequency oscillations observed in GX 13+1 using \textit{AstroSat} (Large Area X-ray Proportional Counter and Soft X-ray…
Spectral evolution of GX 17+2 using AstroSat and NICER observations
Sree Bhattacherjee, Ranjeev Misra, Biplob Sarkar +3
We study the spectral evolution of the Z-track source GX 17+2 using AstroSat and NICER observations taken between 2016 and 2020. The AstroSat observations cover the period when the…
Relativistic Accretors and High Energy X-Ray view
Asish Jyoti Boruah, Liza Devi, Biplob Sarkar
Relativistic accretors are cosmic objects that pull matter from their surroundings at speeds almost equal to the light's speed. Because of the tremendous gravitational force from t…
An Overview of Numerical Simulations in Accretion Physics
Biplob Sarkar, Liza Devi, Asish Jyoti Boruah
Accretion physics studies the process of gravitational capture of ambient matter by massive stars. The background processes are very challenging to observe and measure due to the e…
Spectro-temporal study of atoll source GX 9+9 observed with AstroSat
Sree Bhattacherjee, Arbind Pradhan, Biplob Sarkar
In this work, we performed a spectro-temporal investigation of the low-mass X-ray binary GX 9+9 using the Large Area X-ray Proportional Counter (LAXPC) and Soft X- ray Telescope (S…
Accretion Disc Outbursts and Stability Analysis
Liza Devi, Asish Jyoti Boruah, Biplob Sarkar
Accretion disc outbursts are re-occurring events observed in various astrophysical systems, including X-ray binaries and cataclysmic variables. These outbursts are characterized by…