TITLE:   GCN CIRCULAR
NUMBER:  45940
SUBJECT: GRID detection of GRB 261010A
DATE:    26/10/13 12:32:49 GMT
FROM:    GRID Student Team at Tsinghua University <grid@tsinghua.edu.cn>

# GRID detection of GRB 261010A

Zihan Yu, Chenyu Wang, Xinyu Liu report on behalf of the GRID Collaboration:

GRID-11B reports the detection of the long-duration GRB 261010A, which was also detected by Fermi GBM (GCN Circular 45888, 45911), Swift BAT (GCN Circular 45889, 45918), and Konus-Wind (GCN Circular 45925).

X-ray and optical afterglow detections were reported by Swift XRT (GCN Circular 45889, 45894, 45935), NOT/ALFOSC (GCN Circular 45890, 45912), and the OSN 1.5m telescope (GCN Circular 45891).

We adopt 2026-10-10 at 19:17:03 UTC, the Fermi GBM trigger time, as T0. Using a source interval from T0-2 to T0+8 s, the measured burst duration (T90) using events selected in the 30-2000 keV range of the GRID-11B FITS energy column is approximately 5.4 +/- 1.2 seconds (statistical uncertainty).

The extended emission reported by other instruments is not clearly seen in the GRID-11B light curve. The reported T90 characterizes the main emission episode.

The GRID light curve of this event can be found at https://mirrors.tuna.tsinghua.edu.cn/GRID/data/GRID-GCN/GRB261010A/GRID_261010A_ltcv.pdf .

GRID is a student-led project to monitor the transient gamma-ray sky with multiple detectors onboard different nanosatellites in the era of multi-messenger astronomy. For more information about GRID, please refer to the following references: https://doi.org/10.1007/s10686-019-09636-w and https://doi.org/10.1007/s10686-021-09819-4 .