Study of a Tidal Disruption Event Candidate
Abstract
During the close encounter of a star with a supermassive black hole, the star might get disrupted by the black hole's tidal forces (tidal disruption events, TDE). The accretion of the stellar material onto the black hole creates luminous emission at different wavelength, including X-rays. We will report the results of an investigation of a bright X-ray source in a set of five ROSAT PSPC observations. The light curve of this event shows an increase in brightness by a factor of nine within eight days, followed by a strong fading over the following 165 days. This observation seems inconsistent with common X-ray source variability, such as active galactic nuclei, and more in favor of a TDE. In order to investigate the possible TDE origin, optical and X-ray spectra have been analyzed. An expected absence of emission lines in the optical and a very soft X-ray spectrum are confirmed. Detailed comparisons with known TDEs show discrepancies in the light curves. Particularly, the increase in brightness happens over a shorter timescale than comparable events. The study of this TDE candidate might help to gain a better understanding of such events, especially for the expected TDE discoveries with the upcoming eROSITA all-sky survey.
- Publication:
-
The X-ray Universe 2017
- Pub Date:
- October 2017
- Bibcode:
- 2017xru..conf...96H