GCN Circular 44920
Subject
GRB 260610B / AT2026owq: OASDG optical observations
Event
Date
2026-06-12T07:54:38Z (2 days ago)
Edited On
2026-06-13T14:41:45Z (a day ago)
From
luca.izzo@inaf.it
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of luca.izzo@inaf.it
Via
Web form
L. Izzo (INAF-OACn, DARK/NBI, OASDG) reports:
We observed the counterpart of GRB 260610B (Fermi GBM team, GCN #44901) using the 0.5-m T1 telescope of the Osservatorio Astronomico S. Di Giacomo (OASDG), located in Agerola, Italy. Our observations started on 2026 June 11 at 21:44 UT, 0.917 days after the GRB trigger. We acquired a series of 8 × 300 s images in the Rc and Ic filters.
The optical counterpart, also reported as AT2026owq (O'Neill et al., GCN #44903; Watson et al., GCN #44905; Zhu et al., GCN #44909; Gillanders et al., GCN #44910; Akl et al., GCN #44911; O'Neill et al., GCN #44914; Moskvitin et al., GCN #44918; Perley et al., GCN #44919), is clearly detected in both stacked images.
We measure the following preliminary magnitudes (AB), which have been calibrated against nearby stars from the Pan-STARRS catalog and appropriately transformed to Rc and Ic magnitudes.
Rc = 19.44 +/- 0.16 mag
Ic = 19.28 +/- 0.16 mag