Name: Susmita Das
Affiliation: Presidency University
Conference ID : ASI2022_125
Title : Relation between Hard and Soft X-ray Emission in Two TeV Blazars using Astrosat
Authors : Susmita Das, Ritaban Chatterjee
Abstract Type: Poster
Abstract Category : Extragalactic Astronomy
Abstract : We study several simultaneous hard (3-80 keV) and soft (0.3-8 keV) X-ray light curves of the TeV blazars Mrk 421 and 1ES 1959+650 observed by the SXT and LAXPC instruments onboard AstroSat. The light curves are 45-450 ks long with time bins as short as 250 s and are from multiple epochs during 2016-2019. We calculate the discrete cross-correlation function along with its uncertainty using a model-independent method to probe the inter-band relation. We find that the hard and soft X-ray variability are very well correlated. The time lag is consistent with zero in most pairs of light curves and indicates hard or soft lag in the rest. We comment on possible physical scenarios that may generate the observed time lag and its variation from one epoch to another.