TITLE: GCN CIRCULAR NUMBER: 41902 SUBJECT: LIGO/Virgo/KAGRA S250920bq: Coverage and upper limits from MAXI/GSC observations DATE: 25/09/20 14:43:37 GMT FROM: Satoshi Sugita at Aoyama Gakuin U. <sugita@phys.aoyama.ac.jp> Y. Kawakubo, S. Sugita, M. Serino, H. Hiramatsu, Y. Kondo (AGU) H. Negoro, M. Nakajima, K. Takagi (Nihon U.), N. Kawai, T. Mihara, (RIKEN), report on behalf of the MAXI team: We examined MAXI/GSC all-sky X-ray images (2-20 keV) after compact binary merger candidate S250920bq at 2025-09-20 10:27:39.063 UTC. At the trigger time of S250920bq, the high-voltage of MAXI/GSC was on, but the FOV was out of the 90% credible region of the bayestar skymap. The first one-orbit (92 min) scan observation with GSC after the event covered 100% of the 90% credible region of the bayestar skymap from 10:30:54 to 10:46:39 UTC (T0+195 to T0+1140 sec). No significant new source was found in the region in the one-orbit scan observation. A typical 1-sigma averaged upper limit obtained in one scan observation is 20 mCrab at 2-20 keV. If you require information about X-ray flux by MAXI/GSC at specific coordinates, please contact the submitter of this circular by email. View this GCN Circular online at https://gcn.nasa.gov/circulars/41902. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...