TITLE: GCN CIRCULAR NUMBER: 24339 SUBJECT: GRB 190427A: CALET Gamma-Ray Burst Monitor detection DATE: 19/04/29 07:47:46 GMT FROM: Valentin Pal'shin at AGU N. Cannady (LSU), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), T. Tamura, Y. Shimizu (Kanagawa U), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration: The short GRB 190427A (Swift-BAT trigger #900730: Tohuvavohu et al., GCN Circ. 24261, Ukwatta et al., GCN Circ. 24330; Fermi GBM detection: Malacaria, von Kienlin and Meegan, GCN Circ. 24293) was detected in ground analysis of the CALET Gamma-ray Burst Monitor (CGBM) data near the Swift-BAT trigger time at T0=04:34:14.95 UT on 27 April 2019. The burst signal was seen only by the SGM detector. The source location (Ukwatta et al., GCN Circ. 24330) was out of the HXM detectors' FOVs and likely blocked by the ISS structures. The burst light curve shows a single bin (125 ms) spike with a signal-to-noise ratio of 9.0 in the 40-1000 keV range. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1240374828/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.