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arXiv · 2401.17286

A radio flare associated with the nuclear transient eRASSt J234403-352640: an outflow launched by a potential tidal disruption event

A. J. Goodwin·G. E. Anderson·J. C. A. Miller-Jones·A. Malyali·I. Grotova·D. Homan·A. Kawka·M. Krumpe·Z. Liu·A. Rau
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Abstract

We present an extensive radio monitoring campaign of the nuclear transient eRASSt J234403-352640 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 more than 1000 d, coincident with the X-ray, UV, optical, and infra-red 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 J234403-352640 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.

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A. J. Goodwin, G. E. Anderson, J. C. A. Miller-Jones, A. Malyali, I. Grotova, D. Homan, A. Kawka, M. Krumpe, Z. Liu, A. Rau. 2024-01-30. A radio flare associated with the nuclear transient eRASSt J234403-352640: an outflow launched by a potential tidal disruption event. https://arxiv.org/abs/2401.17286

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