GCN Circular 40839
Subject
GRB 250625A: ABObservatory afterglow detection
Event
Date
2025-06-26T11:06:58Z (a day ago)
From
A. Brosio at ABObservatory Rosarno <antonino.brosio@gmail.com>
Via
Web form
A. Brosio (ABObservatory Rosarno), S. Savaglio (University of Calabria), G. Bracco, P. Cianfarra, L. Sangaletti, S. Tosi & S. Zappatore (University of Genoa), S. Benatti & M. G. Guarcello (INAF Palermo), L.
Cabona, M. Rainer & F. M. Zerbi (INAF Brera), D. Ricci (INAF Padova), A. Di Dato (INAF Capodimonte), S. Masiero & A. Nastasi (GAL Hassin), D. Liguori (Osservatorio "G. Galilei" Cariati), L. Betti (Osservatorio
Polifunzionale del Chianti), R. Nesci (Associazione Astronomica Antares APS di Foligno), for the NOCTIS team report
We observed the field of GRB 250625A, which was detected by Swift-BA (Ferro et al., GCN 40825) and Fermi-GBM (GCN #40824) with the 30-cm automated telescope at ABObservatory (Rosarno, Italy) in clear filter. The observations began on 2025 june 25 at 19:34:37 UT, approximately 3.34 hours after the trigger. The observation consisted of 85 exposures of 90 seconds each, with good sky condictions. The mid-exposure time was 20:21:42 UT, and the final exposure ended at 21:09:59 UT.
From photometry, we detect the optical counterpart in our images at the at the following coordinates:
R.A (J2000.0) = 17:26:01.56
Dec. (J2000.0) = +22 16 12.3
The measured magnitude is:
V = 21.13 +/- 0.28 with SNR 5.4 (AB, calibrated against the Pan-STARRS catalogue on SIMBAD).