The Calorimetric Electron Telescope (CALET) for high energy astroparticle physics on the international space station

The CALET space experiment, currently under development by Japan in collaboration with Italy and the United States, will measure the flux of Cosmic Ray electrons (including positrons) to 20 TeV, gamma rays to 10 TeV and nuclei with Z=1 to 40 up to 1,000 TeV during a five year mission. These measurements are essential to investigate possible nearby astrophysical sources of high energy electrons, study the details of galactic particle propagation and search for dark matter signatures. The instrument consists of a module to identify the particle charge, a thin imaging calorimeter (3 radiation lengths) with tungsten plates interleaving scintillating fiber planes, and a thick calorimeter (27 radiation lengths) composed of lead tungstate logs. CALET has the depth, imaging capabilities and energy resolution necessary for excellent separation between hadrons, electrons and gamma rays. The instrument is currently being prepared for launch, during the 2014 time frame, to the International Space Station (ISS) for installation on the Japanese Experiment Module - Exposed Facility (JEM-EF).