Speaker
Description
The CALorimetric Electron Telescope (CALET) is a high-energy astroparticle physics experiment designed by a Japanese-Italian-US collaboration that has been operating continuously and nearly flawlessly on the International Space Station (ISS) since October 2015. Utilizing a deep, hybrid calorimeter, the mission records approximately 20 million events above 10 GeV per month to precisely measure the spectra of cosmic leptons, hadrons, and photons. CALET is specifically engineered to measure the spectra of electrons and positrons up to 20 TeV (and gamma rays up to 10 TeV), searching for nearby sources of high-energy electrons and signatures of dark matter.
By providing precise charge measurements, the experiment also identifies cosmic nuclei and measures their spectra up to the PeV energy scale to study galactic cosmic-ray acceleration and propagation. Observations have revealed unexpected deviations from a power-law in the spectra of electrons (around 1 TeV), as well as in the spectra of protons, helium, and heavier cosmic nuclei. Furthermore, CALET measures the relative abundances of ultra-heavy galactic cosmic rays (UHGRC) from atomic number Z=28 (nickel) through Z=44 (ruthenium). Beyond high-energy particles, the mission monitors the sky for X-ray and soft gamma-ray transients using the CALET Gamma-Ray Burst Monitor (CGBM), searches for electromagnetic counterparts to LIGO/Virgo gravitational wave events and studies space-weather phenomena. The science results obtained during the first eleven years of CALET operation will be presented and discussed.