X-ray flares from the stellar tidal disruption by a candidate supermassive black hole binary

This paper reports the discovery of delayed X-ray brightening in the tidal disruption event (TDE) OGLE16aaa, approximately 140 days after the optical outburst. This delayed brightening, along with subsequent flux dips, is unusual for standard TDEs and suggests the presence of a supermassive black hole binary (SMBHB) or patchy obscuration. The authors propose that X-rays were initially blocked, possibly by a radiation-dominated ejecta, with reprocessing leading to the observed optical and ultraviolet emission. Their findings highlight the importance of reprocessing in early TDE evolution and the potential of X-ray observations for revealing SMBHBs.

Xinwen Shu, Wenjie Zhang, Shuo Li, Ning Jiang, Liming Dou, Zhen Yan, Fu-Guo Xie, Rongfeng Shen, Luming Sun, Fukun Liu, Tinggui Wang