Unveiling the Temporal Properties of MAXI J1820+070 through AstroSat Observations
We present here the results of the first broadband simultaneous spectral and temporal studies of the newly detected black hole binary MAXI J1820+070 as seen by Soft X-ray Telescope and Large Area X-ray Proportional Counter (LAXPC) on board AstroSat. The observed combined spectra in the energy range 0.7-80 keV were well modeled using disk blackbody emission, thermal Comptonization, and a reflection component. The spectral analysis revealed that the source was in its hard spectral state (? = 1.61) with a cool disk (kT in = 0.22 keV). We report the energy dependent time-lag and root mean squared (rms) variability at different frequencies in the energy range 3-80 keV using LAXPC data. We also modeled the flux variability using a single-zone stochastic propagation model to quantify the observed energy dependence of time lag and fractional rms variability, and then compared the results with that of Cygnus X-1. Additionally, we confirm the detection of a quasi-periodic oscillation with the centroid frequency at 47.7 mHz. 2020. The American Astronomical Society. All rights reserved..
Mudambi S.P.; Maqbool B.; Misra R.; Hebbar S.; Yadav J.S.; Gudennavar S.B.; Bubbly S.G.
Astrophysical Journal Letters, Vol-889, No. 1
All Open Access; Bronze Open Access; Green Open Access
Mudambi S.P., Department of Physics and Electronics, Christ (Deemed to Be University), Bangalore Central Campus, Bengaluru, 560029, India; Maqbool B., Inter-University Centre for Astronomy and Astrophysics, Ganeshkind, Pune, 411007, India; Misra R., Inter-University Centre for Astronomy and Astrophysics, Ganeshkind, Pune, 411007, India; Hebbar S., Department of Physics and Electronics, Christ (Deemed to Be University), Bangalore Central Campus, Bengaluru, 560029, India; Yadav J.S., Department of Physics, Indian Institute of Technology, Kanpur, 208016, India; Gudennavar S.B., Department of Physics and Electronics, Christ (Deemed to Be University), Bangalore Central Campus, Bengaluru, 560029, India; Bubbly S.G., Department of Physics and Electronics, Christ (Deemed to Be University), Bangalore Central Campus, Bengaluru, 560029, India