A radio flare associated with the nuclear transient eRASSt J234403-352640: an outflow launched by a potential tidal disruption event
Abstract
We present an extensive radio monitoring campaign of the nuclear transient eRASSt J234402.9-352640 with the Australia Telescope Compact Array, one of the most X-ray luminous TDE candidates discovered by the SRG/eROSITA all-sky survey. The observations reveal a radio flare lasting >1000 d, coincident with the X-ray, UV, optical, and infrared flare of this transient event. Through modelling of the 10 epochs of radio spectral observations obtained, we find that the radio emission is well-described by an expanding synchrotron emitting region, consisting of a single ejection of material launched coincident with the optical flare. We conclude that the radio flare properties of eRASSt J234402.9-352640 are consistent with the population of radio-emitting outflows launched by non-relativistic tidal disruption events, and that the flare is likely due to an outflow launched by a tidal disruption event (but could also be a due to a new AGN accretion event) in a previously turned-off AGN.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 2024
- DOI:
- 10.1093/mnras/stae362
- arXiv:
- arXiv:2401.17286
- Bibcode:
- 2024MNRAS.528.7123G
- Keywords:
-
- radio continuum: transients;
- transients: tidal disruption events;
- keyword3;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 14 pages, 7 figures, submitted to MNRAS