CALET Overview

The CALET mission will investigate the High Energy Universe, as a next generation experiment to build upon discoveries made by Fermi, PAMELA, AMS, Atmospheric Cherenkov Telescopes (ACT) and balloon instruments. CALET is a calorimeter based instrument which will have superior energy resolution and excellent separation between hadrons and electrons and between charged particles and gamma rays. With these capabilities, it will be possible for CALET to address many of the outstanding questions in High Energy Astrophysics (HEA) including (1) signatures of dark matter, in either the high energy electron or gamma ray spectrum, (2) the nature of the sources of high energy particles and photons, through the high energy electron spectrum, (3) the details of particle propagation in the galaxy, by a combination of energy spectrum measurements of electrons, protons and higher-charged nuclei. Thus, CALET can be thought of as a HEA "observatory".

CALET, an acronym for CALorimeteric Electron Telescope, is a Japanese led international mission being developed as part of the utilization plan for the International Space Station (ISS). CALET will be launched by an H2 rocket utilizing the Japanese developed HTV (H-IIA Transfer Vehicle). The instrument will be robotically emplaced upon the Exposure Facility attached to the Japanese Experiment Module (JEM-EF), as illustrated in Figure 1. The four US institutions collaborating in this proposal were invited by the Japanese team to join CALET, since each institution brings significant experience and expertise derived from previous balloon and satellite experiments. Providing this expertise to help move CALET through the development process and on to launch and on-orbit operations is the task described here. It is the objective of the US collaborators to provide as much help as possible to CALET - since this mission can make a major contribution to the future of High Energy Astrophysics.

The US institutions consist of Lead Institution Louisiana State University (LSU), Goddard Space Flight Center (GSFC), Washington University in St. Louis (WU) and the University of Denver (DU) will be involved with CALET development, testing, pre-launch data, flight operations, flight data processing and science analysis along with the international CALET team.