Abstract Details

Name: Bhuvana GR
Affiliation: Dayananda Sagar University
Conference ID: ASI2020_74
Title : Spectral and timing analysis of LMC X-1 using AstroSat
Authors and Co-Authors : Bhuvana G. R. 1 *, Radhika D. 1 , Anuj Nandi 2 , Vivek K. Agrawal 2 , Mandal S. 3 . 1. Department of Physics, Dayananda Sagar University, Bengaluru. 2. Space Astronomy Group, ISITE campus, U. R. Rao Satellite Centre, Bengaluru. 3. Department of Earth and space Sciences, IIST, Thiruvananthapuram.
Abstract Type : Oral
Abstract Category : Extragalactic Astronomy
Abstract : We have studied the persistent black hole X-ray binary LMC X-1 using data observed by AstroSat during 2016 and 2017 with a time gap of nine months. We explore the spectral and timing variability of the source during these observations using data obtained from SXT (0.5 – 6 keV) and LAXPC (3 - 30 keV). During the first epoch of AstroSat observation (November 2016), the source spectrum are found to be described by a disc blackbody component (kT in ~0.8 keV) and a weak power-law component (г = 2.2 - 2.9) indicating that source is in soft state and during the second epoch (August 2017), the spectra is found to be described by disc blackbody component (kT in ~ 0.8 keV) along with a significant comptonization component (г ~ 1.8) indicating transition of the source to the intermediate state. In addition, a relativistically broadened reflection feature at ~ 6.4 keV has been observed in both epoch of observations. We also examined the temporal variability of LMC X-1 in the energy range of 3 - 30 keV which resulted in rms variability of ~2% for epoch 1, whereas 3 - 4% for epoch 2 over the frequency range of 0.01 - 50 Hz. In addition, energy dependent power spectra and phase lags is also being studied. Further investigation is in progress in order to constrain the mass and spin of the blackhole using AstroSat data.