TITLE:   GCN CIRCULAR
NUMBER:  37448
SUBJECT: LIGO/Virgo/KAGRA S240910ci: Coverage and upper limits from MAXI/GSC observations
DATE:    24/09/10 13:06:47 GMT
FROM:    Yuta Kawakubo at Aoyama Gakuin University <kawakubo@phys.aoyama.ac.jp>

H. Hiramatsu, S. Sugita, M. Serino, Y. Kawakubo, H. Nishikawa, 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 S240910ci at 2024-09-10 10:35:35.495 UTC (GCN #37446, 37447).

At the trigger time of S240910ci, the high-voltage of MAXI/GSC was on.
The instantaneous field of view of GSC at the GW trigger time covered 6% 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 51%
of the 90% credible region of the Bilby skymap from 10:35:35 to 10:45:20 UTC (T0+0 to T0+585 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.