Particle and Astroparticle Physics Seminar

Results from the First Two Years of Operation of the CALorimetric Electron Telescope (CALET) Mission on the International Space Station

Mike Cherry

Louisiana State University

The CALorimetric Electron Telescope (CALET), a Japanese-Italian-US cosmic ray and high-energy astroparticle physics experiment on the International Space Station, has been operating since October 2015. The primary goals of the CALET mission include investigating possible nearby sources of high-energy electrons, studying the details of galactic particle propagation, and searching for dark matter signatures. Over a planned five-year mission, CALET will measure the flux of cosmic- ray electrons and positrons to 20 TeV, gamma-rays to 10 TeV, and nuclei with Z=1 to 40 up to 1000 TeV. The instrument consists of two layers of segmented plastic scintillators for the cosmic-ray charge identification, a 3 radiation length thick tungsten-scintillating fiber imaging calorimeter, and a 27 radiation length thick lead-tungstate calorimeter. CALET has su#cient depth, imaging capabilities and excellent energy resolution to allow for a clear separation between hadrons and electrons and between charged particles and gamma rays.

The rate of the triggered events over 10 GeV is nearly 20 million per month. Based on the data obtained during the first two-years of operation, I will summarize the CALET observations including the Electron + Positron energy spectrum, Proton and Nuclei spectrum, and Gamma-ray observations. I will also present the results of observations of the electromagnetic counterparts to LIGO-VIRGO gravitational wave events and high-energy counterparts to GRB events measured with the CALET Gamma-ray Burst Monitor (CGBM).