GCN Circular 36325
Subject
LIGO/VIRGO/KAGRA S240422ed: Historical variability for EP240426a
Date
2024-04-26T21:26:32Z (7 months ago)
From
Andrew Levan at Radboud University <a.levan@astro.ru.nl>
Via
Web form
A. J. Levan (Radboud), N. R. Tanvir (U. Leicester), D.T.H. Steeghs (Warwick) report for the ENGRAVE collaboration:
The field of EP240426a (Sun et al., GCN 31313), the X-ray transient suggested as a possible counterpart to S240422ed (LVK, GCN 36236), has been observed multiple times in the K-band during 2018-2019 as part of the VISTA Variables in Via Lactea (VVV) survey undertaken with the ESO/VISTA telescope. Image subtraction of several of these images reveals a clear residual signal at the nucleus of 2MASX J08072584-292734.
The presence of past nuclear infrared variability of the source suggests that the most likely origin for both the recent X-ray (Sun et al., GCN 31313) and apparent optical variability (Hu et al., GCN 36317) is due to ongoing AGN variability, and that the source is probably not related to S240422ed.