TITLE:   GCN CIRCULAR
NUMBER:  36831
SUBJECT: EP240702a: TRT optical upper limits
DATE:    24/07/05 15:23:17 GMT
FROM:    S. Tinyanont at National Astronomical Research Institute of Thailand <samaporn@narit.or.th>

S. Tinyanont, R. Anutarawiramkul, P. Butpan (NARIT), S.Q. Jiang, J. An, X. Liu, S.Y. Fu, Z.P. Zhu, D. Xu, Z. Fan, W.X. Li, N.C. Sun, Y.N. Wang (NAOC) report on behalf of a large collaboration:

We observed the field of EP240702a (Chen et al., GCN 36801) using the 0.7-m telescope of the Thai Robotic Telescope (TRT) network, located at Spring Brook Observatory, Australia. Observations started at 14:09:46 UTC on 2024-07-03, i.e., 1.55 day after the EP trigger, and 5 x 360 s  frames in R- & I-band were obtained, respectively.

No uncatalogued optical transient is detected in the stacked images within the 3-arcmin EP/WXT error circle, down to 5-sigma limiting magnitudes of R ~ 21.8 and I ~ 20.7, calibrated with SkyMapper sources in the field.