TITLE: GCN CIRCULAR NUMBER: 38738 SUBJECT: GRB 241229B: SVOM/GRM observation DATE: 24/12/31 08:11:34 GMT FROM: Yue Wang SVOM/GRM team: Yue Wang, Chen-Wei Wang, Shi-Jie Zheng, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP), report on behalf of the SVOM team: The SVOM/GRM was triggered in-flight by GRB 241229B (SVOM trigger reference: sb24122902) at 2024-12-29T01:36:17.000 UT (T0), which was also observed by Fermi/GBM (Fermi GBM Team, GCN 38698) and Swift/BAT (A. D'Ai et al, GCN 38699). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of one main pulse with a T90 of 5.45 +0.76/-1.01 s This burst is located (from Swift/BAT) at about 57.10 degrees from the SVOM optical axis, and outside the ECLAIRs field of view. The GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb241229B.png The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), 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: Yue Wang (IHEP)(yuewang@ihep.ac.cn)