Monthly quasi-periodic eruptions from repeated stellar disruption by a massive black hole

Understand

In recent years, searches of archival X-ray data have revealed galaxies exhibiting nuclear quasi-periodic eruptions with periods of several hours.

• These are reminiscent of the tidal disruption of a star by a supermassive black hole, and the repeated, partial stripping of a white dwarf in an eccentric orbit around a ~10^5 solar mass black hole provides an attractive model.
• A separate class of periodic nuclear transients, with significantly longer timescales, have recently been discovered optically, and may arise from the partial stripping of a main-sequence star by a ~10^7 solar mass black hole.
• No clear connection between these classes has been made.