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GCN Circular 34854

LIGO/Virgo/KAGRA S231020ba: Coverage and upper limits from MAXI/GSC observations
2023-10-20T17:24:16Z (7 months ago)
Yuta Kawakubo at Louisiana State University <>
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Y. Kawakubo (LSU),
H. Negoro, M. Nakajima (Nihon U.), 
T. Mihara (RIKEN), N. Kawai (RIKEN), 
S. Sugita, M. Serino, 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 S231020ba at 2023-10-20 14:29:47.000 UTC (GCN #34852). 

At the trigger time of S231020ba, the high-voltage of MAXI/GSC was off, 
and it was turned on at T0+1153 sec (+19.2 min). 
The first one-orbit (92 min) scan observation with GSC after the event covered 90% 
of the 90% credible region of the bayestar skymap from 14:51:52 to 16:00:18 UTC (T0+1325 to T0+5431 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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