Quasi-periodic X-ray eruptions years after a nearby tidal disruption event.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39385028.
- Also identified by DOI 10.1038/s41586-024-08023-6 and PMC identifier 11499261.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Quasi-periodic eruptions (QPEs) are luminous bursts of soft X-rays from the nuclei of galaxies, repeating on timescales of hours to weeks<sup>1-5</sup>. The mechanism behind these rare systems is uncertain, but most theories involve accretion disks around supermassive black holes (SMBHs) undergoing instabilities<sup>6-8</sup> or interacting with a stellar object in a close orbit<sup>9-11</sup>. It has been suggested that this disk could be created when the SMBH disrupts a passing star<sup>8,11</sup>, implying that many QPEs should be preceded by observable tidal disruption events (TDEs). Two known QPE sources show long-term decays in quiescent luminosity consistent with TDEs<sup>4,12</sup> and two observed TDEs have exhibited X-ray flares consistent with individual eruptions<sup>13,14</sup>. TDEs and QPEs also occur preferentially in similar galaxies<sup>15</sup>. However, no confirmed repeating QPEs have been associated with a spectroscopically confirmed TDE or an optical TDE observed at peak brightness. Here we report the detection of nine X-ray QPEs with a mean recurrence time of approximately 48 h from AT2019qiz, a nearby and extensively studied optically selected TDE<sup>16</sup>. We detect and model the X-ray, ultraviolet (UV) and optical emission from the accretion disk and show that an orbiting body colliding with this disk provides a plausible explanation for the QPEs.