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GCN Circular 36238

LIGO/Virgo/KAGRA S240422ed: Coverage and upper limits from MAXI/GSC observations
2024-04-23T00:40:03Z (3 months ago)
Yuta Kawakubo at Aoyama Gakuin University <>
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N. Kawai (RIKEN), H. Negoro, M. Nakajima (Nihon U.),
T. Mihara (RIKEN),
S. Sugita, M. Serino, Y. Kawakubo, H. Hiramatsu, H. Nishikawa, Y. Kondo (AGU)
report on behalf of the MAXI team:

We examined MAXI/GSC all-sky X-ray images (2-20 keV)
after compact binary merger candidate S240422ed at 2024-04-22 21:35:13.417 UTC (GCN #36236).

At the trigger time of S240422ed, the high-voltage of MAXI/GSC was off,
and it was turned on at T0+620 sec (+10.3 min).
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 22:32:11 to 22:37:06 UTC (T0+3418 to T0+3713 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. 
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