GCN Circular 46249
Subject
GRB 261113A: GMG Optical Observation
Event
Date
2026-11-13T16:36:35Z (2 days ago)
From
Rui-Zhi Li at Yunnan Observatories, CAS <liruizhi@ynao.ac.cn>
Via
Web form
R.-Z. Li, B.-T. Wang, F.-F. Song, J. Mao, J.-G. Wang and B. Wang (YNAO, CAS) report:
We observed the field of GRB 261113A (Saccardi et al., GCN 46244, T0 at 2026-11-13T14:31:02) using the GMG-2.4m telescope at the Lijiang Observatory.
The observation began at 2026-11-13T15:23:45, about 0.88 hours after the trigger.
The optical counterpart (Lin et al., GCN 46247; Lei et al., GCN 46248) was well detected in our r-band image.
The preliminary analysis results are shown as follows:
Start time [UTC] Exposure [s] Tmid-T0 [h] Filter AB Magnitude 5-sigma U.L.
----------------------- -------------- ------------- -------- -------------- --------------
2026-11-13 15:23:45.073 300 0.92 r 19.39 ± 0.02 22.3
The given magnitudes are derived based on calibration against Pan-STARRS field stars, and are not corrected for the expected Galactic foreground extinction, corresponding to a reddening of E(B-V) = 0.052 mag in the direction of the optical counterpart (Schlafly & Finkbeiner 2011).