GCN Circular 41385

SVOM/GRM team: Chen-Wei Wang, Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP)

SVOM/ECLAIRs team: Hui Yang (IRAP), Stéphane Schanne (CEA)

Report on behalf of the SVOM team:

SVOM/GRM was triggered in-flight by a short burst GRB 250814C (SVOM trigger reference: sb25081402) at 2025-08-14T03:24:23.000 UTC (T0), which is also detected by Konus-Wind and Swift/BAT.

With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of multi-pulses with a T90 of 1.20 +0.20/-0.30 s in the 15-5000 keV band.

The SVOM/GRM light curve can be found here:
https://www.bursthub.cn//admin/static/svgrb250814C.png

There is no indication of any subthreshold target from both CRT and IMT triggers onboard ECLAIRs close to the time of this event, suggesting that it is either too weak to be detected or outside the FoV of ECLAIRs.

The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS.

The SVOM point of contact for this burst is: Chen-Wei Wang (IHEP)(cwwang@ihep.ac.cn)