GCN Circular 35210

Wen-Long Zhang, Shao-Lin Xiong report on behalf of the GECAM team:

GECAM-C was triggered in-flight by a long burst, GRB 231129A, at 2023-11-29T05:06:01.850 UTC (T0), which was also observed by Swift/BAT (GCN #35208) and INTEGRAL (GCN #35209). 

According to the realtime alert data, the GECAM-C light curve shows roughly two peaks with a total duration of ~80 sec (15-1050 keV). 

The time-averaged spectrum of GECAM-C realtime data from about T0 to T0+4 s could be
adequately fit by a cut-off power-law with a fluence about 1.84E-6 erg/cm^2 in 20-1000 keV. 

GECAM location is consistent with that of Swift/BAT and INTEGRAL within the error.
We note that these results are based on realtime alert data and thus very preliminary. Refined analysis will be reported later.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).