GCN Circular 45865
Subject
GRB 261007A: NOT optical observations
Event
Date
2026-10-08T16:07:48Z (3 hours ago)
From
d.s.oneill@bham.ac.uk
Via
Web form
D. O’Neill (Birmingham), D. B. Malesani (DAWN/NBI), A. S. Mårtensson (NOT), A. Caballero Almagro (NOT), report on behalf of a larger collaboration:
We observed the optical counterpart (Zheng et al., GCN 45825; Saccardi et al., GCN 45829; Mohan et al., GCN 45832; Saccardi et al., GCNs 45837, 45837; Shi et al., GCN 45838; An et al., GCN 45840; Arya et al., GCN 45841; Rehemtulla et al., GCN 45843; Ruiz-Laguna et al., GCN 45844; Angulo et al., GCN 45848; Li et al., GCN 45851; Chen et al., GCN 45855; Zhang et al., GCN 45856) of GRB 261007a/EP261007a (Fermi GBM team, GCN Circ. 45830; SVOM/ECLAIRs: Goto et. al., GCN Circ. 45824; SVOM/GRB: Ren et al., GCN 45863; Einstein Probe: Wen et. al., GCN Circ. 45828; NuSTAR: Waratkar et. al., GCN Circ. 45846; AstroSat CZTI: Harsha et. al., GCN 45859) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC instrument. Observations were performed starting at 01:38:38 UT on October 8 2026 (about 20 hr after SVOM trigger), and consisted of 3x300 s in the SDSS-r band.
In our stacked images we measure an AB magnitude:
r = 21.36 ± 0.04
This magnitude is calibrated using nearby objects from the Pan-STARRS catalog and is not corrected for Galactic extinction.