GCN Circular 38768
Subject
GRB 250101A: OASDG optical observations
Date
2025-01-01T23:37:38Z (7 days ago)
From
luca.izzo@inaf.it
Via
Web form
L. D'Avino (OASDG/AstroCampania), and L. Izzo (INAF-OACn and DARK/NBI) report:
We observed the field of GRB 250101A (Page et al., GCN #38752) using the 0.5-m T1 telescope of the Osservatorio Astronomico S. Di Giacomo, located in Agerola, Italy. Our observations started on 2025 January 1 at 16:57 UT, approximately 3.6 hours after the GRB trigger. We acquired a series of 8x300 s frames in the Rc and Ic filters.
In the stacked images, we clearly detect the optical counterpart initially identified by Swift-UVOT (Page et al., GCN #38752) and reported by several other telescopes (Li et al., GCN #38753; Mohan et al., GCN #38754; Zhu et al., GCN #38755; Budnev et al., GCN #38756; Wu et al., GCN #38758; Zhu et al., GCN #38759; Moskvitin et al., GCN #38762, GCN #38765; Odeh & Guessoum, GCN #38763; Hu et al., GCN #38764). We measure a preliminary magnitude of Rc = 20.00 +/- 0.07 mag (AB), calibrated against nearby stars from the Pan-STARRS catalog, appropriately transformed to Rc and Ic magnitudes.