Late time radio re-brightening of the tidal disruption event AT2020vwl
ATel #16165; Adelle Goodwin (Curtin U.), James Miller-Jones (Curtin U.), Kate D. Alexander (Arizona), Clement Bonnerot (Birmingham) Collin T. Christy (Arizona), Tanmoy Laskar (Utah), Dheeraj R. Pasham, and Enrico Ramirez-Ruiz (UCSC)
on 31 Jul 2023; 12:23 UT
Credential Certification: Adelle Goodwin (adelle.goodwin@curtin.edu.au)
Subjects: Radio, Transient, Tidal Disruption Event
We report on a late time radio re-brightening of the tidal disruption event (TDE) AT2020vwl. The TDE was originally discovered by the Zwicky Transient Facility (ZTF) on 2020 October 8 and classified as a TDE on 2021 January 15 due to transient broad He II and Balmer lines in a follow-up optical spectrum and bright UV flux.
AT2020vwl showed fading radio emission between 2021 February 3 and 2022 May 8 (
Goodwin et al 2023 ). We have been monitoring
AT2020vwl with an approximately 3 month cadence with the NRAOâs Karl G. Jansky Very Large Array (VLA) since the 2022 May 8 radio observations reported in Goodwin et al (2023).
On 2023 April 1 we observed AT2020vwl with the VLA as part of our ongoing monitoring campaign. The data were reduced in CASA following standard procedures. We report a flux density measurement of the source at 5.5 GHz (C band) of 404+/-22 uJy, which is brighter by a factor of 2 compared to a previous 5.5 GHz flux density measurement of 179+/-17 uJy on 2022 May 8 (Goodwin et al., 2023), indicating a significant re-brightening of the radio emission.
Further VLA observations are planned in order to characterise the spectral shape and the rate at which the source is brightening. We encourage additional multiwavelength follow-up to aid in characterising the cause of this re-brightening.
References: Goodwin et al, 2023, MNRAS, 522, 4, pp.5084-5097
