LIGO/Virgo G296853 : MAXI/GSC observations

We examined the MAXI/GSC all-sky X-ray images (2-20 keV) obtained in the orbit and the day after the LVC trigger G296853 at 2017-08-09 08:28:21.747 UTC (GCN 21431). At the trigger time of G296853, the high-voltage of MAXI/GSC was off, and it was turned on at T0+1114 sec. GSC scanned more than 83% of the whole sky in the 92-min orbit, which includes 92.7% of the 90% region in the bayestar skymap scanned from 08:49:51 to 09:00:11 UTC (T0+1289 to 1909 sec). One day image obtained between 08-09 08:49:51 and 08-10 08:09:40 UTC covers 100% of the 90% region in the bayestar skymap. No significant new source was found in these images. The 2-20 keV 1-sigma (3-sigma) averaged upper limits obtained from the one-orbit and one-day images in the bayestar skymap are 12(36) and 3(9) mCrab, respectively. If you require information of X-ray flux by MAXI/GSC at specific coordinates, please contact the submitter of this circular by email.