TITLE: GCN CIRCULAR NUMBER: 38451 SUBJECT: GRB 241206B: GWAC-F50A optical upper limit DATE: 24/12/06 16:29:06 GMT FROM: Liping Xin at NAOC, SVOM <xlp@nao.cas.cn> SVOM/GWAC-F50A team：L.P.Xin(NAOC), Y.G.Yang(HNU), C.WU(NAOC), Y.L.Qiu(NAOC), J.Wang(NAOC), H.L.Li(NAOC), E.W.Liang(GXU), X.H.Han (NAOC), X.M.Lu(NAOC), R.S.Zhang(NAOC), Y.Xu(NAOC), L. Huang(NAOC), H.B.Cai(NAOC), Y.J.Xiao(NAOC), P.P.Zhang(NAOC), L.Lan(NAOC), W.J.Xie(NAOC), Z.H.Yao(NAOC), X.G.Wang (GXU), J.Y.Wei(NAOC) SVOM JSWG: Jian-Yan Wei (NAOC), Bertrand Cordier (CEA), Shuang-Nan Zhang (IHEP), Stéphane Basa (LAM), Olivier Godet (IRAP), Arnaud Claret (CEA), Zi-Gao Dai (USTC), Frédéric Daigne (IAP), Jin-Song Deng (NAOC), Andrea Goldwurm (APC), Diego Götz (CEA), Xu-Hui Han (NAOC), Cyril Lachaud (APC), En-Wei Liang (GXU), Yu-Lei Qiu (NAOC), Susanna Vergani (Obs.Paris), Jing Wang (NAOC), Chao Wu (NAOC), Li-Ping Xin (NAOC), Bing Zhang (UNLV) Report on behalf of the SVOM team: We began to observe GRB 241206B (Saccardi et al., GCN 38450), with 50cm telescope (GWAC-F50A) at Xinglong station, China, at 2024-12-06T15:38:26.8 (UT), about 19.7 min after the burst. With the initial observation with exposure time of 50 sec, no any uncatalogued source was detected in our image down to a limit magnitude of 17.0 mag in R band comparing to several nearby USNO B1.0 stars. We acknowledge the excellent support from observation assistant Yangtong Zheng and Winlong Dong. View this GCN Circular online at https://gcn.nasa.gov/circulars/38451. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...