Abstract Details

Name: Sriram Kandulapati
Affiliation: Department of Astronomy, Osmania University, Hyderabad
Conference ID: ASI2020_173
Title : Constraining the coronal height and readjustment velocities using lags obtained from RXTE and NuStar observations of Z source GX
Authors and Co-Authors : K. Sriram, Malu S.
Abstract Type : Poster
Abstract Category : Stars, ISM and Galaxy
Abstract : Using the energy dependent CCF analysis of RXTE and NuStar data we attempt to constrain the coronal height and readjustment velocities in GX 17+2. CCF studies revealed correlated and anti correlated hard (16-30 keV) and soft (2-5 keV) lags of the order of a few hundred seconds which is characteristic of the Horizontal and Normal branch. These lags are assumed to be readjustment time scales of the disk-corona structure and the coronal heights were estimated, which came out to be 17-100 km. Here the primary contribution to the lags is found to be due to coronal readjustment as the disk readjustment velocities were found to be much lower. Upon considering a ratio β which is defined as the ratio of readjustment velocity of disk to the corona and taking the coronal height to be equal to the truncated radius of the accretion disk we find the coronal readjustment velocities to be ~ 0.06-0.12 times the readjustment velocities of disk.