On-orbit operation and gamma-ray burst observations with the CALET Gamma-ray Burst Monitor

The CALorimetric Electron Telescope (CALET) includes a Gamma-ray Burst Monitor (CGBM) to enhance the gamma-ray observations of the calorimeter, the main CALET detector. CGBM consists of two kinds of scintillation detectors, the Hard X-ray Monitor (HXM) consisting of LaBr₃(Ce) and the Soft Gamma-ray Monitor (SGM) consisting of BGO. Together, the two detectors cover the X-ray/gamma-ray energy range 7 keV - 20 MeV. CGBM has observed gamma-ray bursts (GRBs) since October 2015. So far, CGBM has detected ~140 GRBs. The fraction of long and short GRBs are ~90% and ~10%. In this paper, we describe the current operational status of CGBM, the GRB analysis results including temporal and spectral analysis, and the search for gravitational wave counterparts.