GRB 200605A: CALET Gamma-Ray Burst Monitor detection

The short GRB 200605A (Fermi GBM Localization: the Fermi GBM team, GCN Circ. 27892; IPN triangulation: Hurley et al., GCN Circ. 27900; https://gcn.gsfc.nasa.gov/other/200605A.gcn3) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 18:17:42.317 UTC on 5 June 2020. The burst signal was seen by only the SGM detector. The source location was outside the FOV of the HXM detectors. Because of a problem in one of the ground alert processing script, the GCN notice was not distributed automatically for this event. The burst light curve shows a double-peaked pulse which starts at T-0.176 sec, peaks at -0.048 sec and ends at T+0.256 sec. The T90 and T50 durations measured by the SGM data are 0.368 +- 0.062 sec and 0.232 +- 0.051 sec (40-1000 keV), respectively. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1275416255/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.