GCN Circular 39441
Subject
EP250223a: OASDG optical observations
Date
2025-02-24T00:06:24Z (19 days ago)
From
luca.izzo@inaf.it
Via
Web form
L. Izzo (INAF-OACn and DARK/NBI), and D. B. Malesani (DAWN/NBI and Radboud Univ.) report:
We observed the field of EP250223a (Lian et al., GCN #39429) using the 0.5-m T1 telescope of the Osservatorio Astronomico S. Di Giacomo, located in Agerola, Italy. Our observations started on 2025 February 23 at 18:15 UT, approximately 3.19 hours after the GRB trigger. We acquired a series of 6x300 s images in the Rc filter.
In the stacked image, we detect a faint source consistent with the X-ray afterglow reported by EP/FXT (Lian et al., GCN #39429), and by Swift-XRT (Kennea et al., GCN #39437), and with the optical counterpart reported by several other telescopes (Hauptmann et al., GCN #39436; Levan et al., GCN #39438; Wu et al., GCN #39439; Perez-Fournon et al., GCN #39440). We measure a preliminary magnitude of Rc = 19.6 +/- 0.2 mag (AB), calibrated against nearby stars from the Pan-STARRS catalog.