Calorimetric Electron Telescope (CALET) to observe cosmic-ray electrons and gamma-rays on the International Space Station

We have proposed to make observations of high energy cosmic rays with CALET (CALorimetric Electron Telescope) on the International Space Station. Our main objective is to observe electrons up to 20 TeV to investigate origin and propagation of electrons in the Galaxy. Acceleration in nearby supernovae can lead to contributions to the electron spectrum in energies up to tens of TeV. Balloon experiments have observed an excess at sub TeV energies, which could, according to some models, be associated with dark matter particles. CALET will be able to confirm the anomaly with high energy resolution and high statistics. Gamma-rays from 20 MeV to 10 TeV and nuclei up to 1000 TeV can be also observed by CALET. We have finished the conceptual design for CALET. The selection process for the next phase is scheduled for mid-2009. If approved, CALET will be launched in 2013 and will be placed at the Japanese Experiment Module-Exposed Facility (JEM-EF) at the International Space Station (ISS).