GCN Circular 24288
Subject
GRB 190427A: MITSuME Akeno optical upper limits
Date
2019-04-27T15:58:22Z (5 years ago)
From
Katsuhiro L. Murata at Nagoya U <murata@u.phys.nagoya-u.ac.jp>
K. L. Murata, M. Oeda, K.Shiraishi, K. Iida, M. Niwano, R. Adachi, Y.
Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME
collaboration:
We searched for the optical counterpart of GRB 190427A (Tohuvavohu et al.,
GCN Circular #24261) 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 13:16:48 UT. We did not find any new point
sources within the BAT circle (Tohuvavohu et al., GCN Circular #24261) in
all three bands.
We obtained the following 5-sigma limits for the magnitudes.
T0+[hour] MID-UT T-EXP[sec] 5-sigma limits
------------------------------------------------------------------------------------------------
~8.7 13:35:08 1620(g'),1560(Rc),1980(Ic) g'>17.8,Rc>18.2,Ic
>18.6
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
The magnitudes are expressed in the AB system.