TITLE:   GCN CIRCULAR
NUMBER:  40665
SUBJECT: EP250610a: REM optical/NIR observations
DATE:    25/06/10 12:20:35 GMT
FROM:    Riccardo Brivio at INAF-OAB <riccardo.brivio@inaf.it>

R. Brivio, M. Ferro, P. D'Avanzo, S. Covino, D. Fugazza (INAF-OAB) report on behalf of the REM team:

We observed the field of EP 250610a detected by EP/WXT (Zhang et al., GCN 40660) with the REM 60 cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, and H bands, started on 2025 June 10 at 05:02:09 UT (i.e. 36 min after the burst), and lasted for about 1 hour.

From preliminary inspection, we do not detect any possible counterpart at the position of the candidate detected by Swift/XRT (source 1, Evans et al., GCN 40662) down to the following 3sigma limits:

r > 18.7 (AB; calibrated against the Pan-STARRS catalogue),
at a mid-time of 66 min after the trigger;

H > 16.6 (Vega; calibrated against the 2MASS catalogue),
at a mid-time of 39 min after the trigger.