LIGO/Virgo/KAGRA S241109bn: Coverage and upper limits from MAXI/GSC observations

We examined MAXI/GSC all-sky X-ray images (2-20 keV) after compact binary merger candidate S241109bn at 2024-11-09 11:59:24.899 UTC (GCN 38142, 38149). At the trigger time of S241109bn, the high-voltage of MAXI/GSC was on. The instantaneous field of view of GSC at the GW trigger time covered 1% of the 90% credible region of the Bilby sky map, in which we found no significant new X-ray source. The first one-orbit (92 min) scan observation with GSC after the event covered 68% of the 90% credible region of the Bilby skymap from 11:59:24 to 13:31:23 UTC (T0+0 to T0+5519 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.