A stochastic propagation model to the energy dependent rapid temporal behaviour of Cygnus X-1 as observed by AstroSat in the hard state
Bari Maqbool,Sneha Prakash Mudambi,Ranjeev Misra,J. S. Yadav,Shivappa B. Gudennavar,S. G. Bubbly,Ashwini Rao,S Jogadand,M. K. Patil,Sudip Bhattacharyya,K. P. Singh +10 more
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TLDR
In this paper, a fluctuation propagation model for a simple geometry of a truncated disk with a hot inner region was proposed to explain the energy dependent fractional root mean square (rms) and time-lag at different frequencies.Abstract:
We report the results from analysis of six observations of Cygnus X-1 by Large Area X-ray Proportional Counters (LAXPC) and Soft X-ray Telescope (SXT) on-board AstroSat, when the source was in the hard spectral state as revealed by the broad band spectra. The spectra obtained from all the observations can be described by a single temperature Comptonizing region with disk and reflection components. The event mode data from LAXPC provides unprecedented energy dependent fractional root mean square (rms) and time-lag at different frequencies which we fit with empirical functions. We invoke a fluctuation propagation model for a simple geometry of a truncated disk with a hot inner region. Unlike other propagation models, the hard X-ray emission (> 4 keV) is assumed to be from the hot inner disk by a single temperature thermal Comptonization process. The fluctuations first cause a variation in the temperature of the truncated disk and then the temperature of the inner disk after a frequency dependent time delay. We find that the model can explain the energy dependent rms and time-lag at different frequencies.read more
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Unveiling the Temporal Properties of MAXI J1820+070 through AstroSat Observations
Sneha Prakash Mudambi,Bari Maqbool,Ranjeev Misra,Sabhya Hebbar,J. S. Yadav,Shivappa B. Gudennavar,S. G. Bubbly +6 more
TL;DR: In this article, the results of the first broadband simultaneous spectral and temporal studies of the newly detected black hole binary MAXI J1820+070 as seen by SXT and LAXPC on-board AstroSat are presented.
Journal ArticleDOI
Spectral and Timing Properties of the Galactic X-Ray Transient Swift J1658.2-4242 Using Astrosat Observations
TL;DR: In this article, the authors presented the X-ray timing and spectral analysis of the new Galactic Xray transient Swift J1658.2-4242 observed with LAXPC and SXT instruments onboard NASA's Astrosat.
Journal ArticleDOI
Unveiling the temporal properties of MAXI J1820+070 through AstroSat observations
Sneha Prakash Mudambi,Bari Maqbool,Ranjeev Misra,Sabhya Hebbar,J. S. Yadav,Shivappa B. Gudennavar,Bubbly S. G +6 more
TL;DR: In this article, the results of the first broadband simultaneous spectral and temporal studies of the newly detected black hole binary MAXI J1820+070 as seen by SXT and LAXPC on-board AstroSat are presented.
Journal ArticleDOI
Broad-band spectral and timing properties of MAXI J1348–630 using AstroSat and NICER observations
TL;DR: In this paper, the authors present broadband X-ray spectral-timing analysis of the new Galactic Xray transient MAXI~J1348--630 using five simultaneous {\it AstroSat} and {\it NICER} observations.
Journal ArticleDOI
LAXPC instrument onboard AstroSat: Five exciting years of new scientific results specially on X-ray binaries
J. S. Yadav,P. C. Agrawal,Ranjeev Misra,Jayashree Roy,Mayukh Pahari,Mayukh Pahari,R. K. Manchanda +6 more
TL;DR: AstroSat/LAXPC was designed to usher in a new era in rapid variability studies and wide spectral band measurements of the X-ray binaries as discussed by the authors, and it has successfully achieved to a significant extent these Science goals.
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