| Name: | SAJAD AHMAD BOKED |
| Affiliation: | UNIVERSITY OF KASHMIR |
| Conference ID : | ASI2024_565 |
| Title : | Time resolved spectroscopy of a GRS 1915+105 flare during its unusual low state using AstroSat. |
| Authors : | Sajad Boked, Bari Maqbool, V. Jitesh, Ranjeev Misra, Naseer Iqbal, Yashpal Bhulla |
| Authors Affiliation: | 1 SAJAD BOKED (Department of Physics, University of Kashmir, Srinagar 190006, India)
2 BARI MAQBOOL (Islamic University of Science and Technology Awantipora, Pulwama 192122, India)
3 V. JITESH (Department of Physics and Electronics, CHRIST (Deemed to be University), Hosur Main Road, Bengaluru - 560029, India)
4 RANJEEV MISRA (Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007, India)
5 NASEER IQBAL (Department of Physics, University of Kashmir, Srinagar 190006, India)
6 YASHPAL BHULLA (Pacific Academy of Higher Education and Research University, Udaipur-313003,India) |
| Mode of Presentation: | Poster |
| Abstract Category : | High Energy Phenomena, Fundamental Physics and Astronomy |
| Abstract : | Since its discovery in 1992, GRS 1915+105 has been among the brightest sources in the X-ray sky. However, in early 2018,
it dimmed significantly and has stayed in this faint state ever since. We report on AstroSat and NuSTAR observation of GRS
1915+105 in its unusual low/hard state during 2019 May. We performed time-resolved spectroscopy of the X-ray flares observed
in this state and found that the spectra can be fitted well using highly ionised absorption models. We further show that the spectra
can also be fitted using a highly relativistic reflection dominated model, where for the lamp post geometry, the X-ray emitting
source is always very close to the central black hole. For both interpretations, the flare can be attributed to a change in the
intrinsic flux, rather than dramatic variation in the absorption or geometry. These reflection dominated spectra are very similar
to the reflection dominated spectra reported for Active Galactic Nuclei in their low flux states. |
