GCN Circular 37091
Subject
EP240806A: Liverpool Telescope optical follow-up observations
Date
2024-08-07T16:01:03Z (a month ago)
From
A. Bochenek at Liverpool John Moores University <a.m.bochenek@2023.ljmu.ac.uk>
Via
Web form
A. Bochenek and D. A. Perley (LJMU) report:
We observed the field of the fast X-ray transient EP240806a (Wu et al., GCN 37063) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained 5x150s exposures in each of the SDSS r and i filters starting at 2024-08-07 01:47:29 UT, approximately 21 hours after the trigger.
Each set of images was stacked after discarding the last exposure in the r-band because of telescope tracking issues. We report a faint detection in the r-band of r = 22.65 ± 0.22 mag at a position consistent with the optical counterpart reported by Li et al. (GCN 37064). There is no detection in the i-band observation, with the limiting magnitude of i > 21.9 mag (AB) for a three-sigma detection limit:
MJD (mid) T_mid - T_0 Exp time Filter Mag. (AB)
60529.07844 21.08 h 4x150s r 22.65 ± 0.22
60529.08929 21.34 h 5x150s i > 21.9
The photometry was obtained using nearby PanSTARRS secondary standards and was not corrected for extinction.