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GCN Circular 27824

GRB 200524A: optical upper limits from further MITSuME Akeno observation
2020-05-26T07:22:56Z (4 years ago)
Ryohei Hosokawa at Tokyo Institute of Technology <>
R. Hosokawa, N. Nakamura, K. L. Murata, R. Adachi, M. Niwano, F.
Ogawa, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the
MITSuME collaboration:

We performed further observation of the field of GRB 200524A
(Fermi-LAT detection: Dirirsa et al., GCN #27797, Fermi-GBM detection:
Pookalil et al., GCN #27809, Swift-XRT afterglow detection: Capalbi et
al. GCN #27811, and others) with the optical three color (g', Rc, and
Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno
Observatory, Yamanashi, Japan.

The observation started on 2020-05-25 11:27:25.65 UT. We did not
detect the optical afterglow (Ho et al., GCN #27799, Kumar et al., GCN
#27800, Rumyantsev et al., GCN #27802, Sanwal et al., GCN #27803,
Perley et al., GCN #27805, Kumar et al., GCN #27806, de Ugarte Postigo
et al., GCN #27807, Blazek et al., GCN #27810, Ogawa et al., GCN
#27813, Zheng et al., GCN #27814, Izzo et al., GCN #27817, Belkin et
al., GCN #27820, Belkin et al., GCN #27821) in the stacked images. We
obtained the 5-sigma limits as follows.

T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
30.5 2020-05-25 11:34:26 660 g'>18.7, Rc>18.7, Ic>18.0
T0+: Elapsed time after the burst
T-EXP: Total Exposure time

We used the GSC2.3 catalog for flux calibration. The magnitudes are
expressed in the Vega system. The images were processed in real-time
through the MITSuME GPU reduction pipeline (Niwano et al. ,in prep;
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