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GCN Circular 31137

GRB 211129A: MITSuME Akeno optical upper limits
2021-11-29T10:36:23Z (2 years ago)
Ryohei Hosokawa at Tokyo Institute of Technology <>
R. Yamaguchi, R. Hosokawa, Y. Imai, K. L. Murata, M. Niwano, Y.
Takamatsu, N. Ito, R. Noto, S. Sato, M. Takaku, Y. Yatsu, and N. Kawai
(TokyoTech) report on behalf of the MITSuME collaboration:

We observed the field of GRB 211129A(J.D. Gropp et al. GCN Circular
#31136) with the optical three color (g', Rc, and Ic) CCD cameras
attached to the MITSuME 50 cm telescope Akeno. The observation with a
series of 10 sec exposures started at 2021-11-29 09:52:06 UT (60
seconds after Swift trigger). We stacked the images with good
conditions. We did not detect any uncatalogued sources within the XRT
error region (J.D. Gropp et al. GCN Circular #31136). We obtained the
5-sigma limits of the stacked images as follows.

T0+[sec] MID-UT T-EXP[sec] 5-sigma limits
159 2021-11-29 09:53:45 70 g'>17.0, Rc>17.3, Ic>16.4
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time

We used PS1 catalog for flux calibration.
The magnitudes are expressed in the AB system.
The images were processed in real-time through the MITSuME GPU
reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages
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