Discovery of a New Flaring Class in GRS 1915+105 Using AstroSat
The highly variable black hole X-ray binary GRS 1915+105 has shown many flaring classes when the source oscillates between the high soft state (HS) and the hard intermediate state with a transition time of less than 10 s. The X-ray flux is anticorrelated with the hardness ratio (HR2) during these X-...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
IOP Publishing
2025-01-01
|
| Series: | The Astrophysical Journal |
| Subjects: | |
| Online Access: | https://doi.org/10.3847/1538-4357/adc381 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The highly variable black hole X-ray binary GRS 1915+105 has shown many flaring classes when the source oscillates between the high soft state (HS) and the hard intermediate state with a transition time of less than 10 s. The X-ray flux is anticorrelated with the hardness ratio (HR2) during these X-ray flaring classes. We have analyzed Astrosat/Large Area X-ray Proportional Counter and Soft X-ray Telescope data and report here a new X-ray flaring class named η class when the source oscillates between two HS states (the power-law index is always greater than 4) with transition time around 50 s. The X-ray flux is correlated with the hardness ratio. This class is quasi-regular, and we have detected high-frequency quasiperiodic oscillations around 70 Hz during this new flaring class. The accretion rate changes by a factor of 3 over the burst cycle. We report here the results of our extensive study of spectral and timing characteristics of this new class. |
|---|---|
| ISSN: | 1538-4357 |