Prospects of gamma-ray observations and dark matter search with CALET

We are developing the CALET (CALorimetric Electron Telescope) instrument for the observation of high-energy electrons and gamma rays at the Exposed Facility of the Japanese Experiment Module on the International Space Station (ISS). CALET has a capability to observe electrons (+positrons) in 1 GeV-10 TeV and gamma rays in 20 MeV-10 TeV with a high energy resolution of < 2 % over 100 GeV, a good angular resolution of 0.06 deg at 100 GeV, and a high proton rejection power of 10⁶. CALET has the geometrical factor of nearly 0.8 m2sr and three-years observation is expected. Thus, CALET is a complementary gamma-ray detector with GLAST, HESS and so on. In particular, the excellent energy resolution of CALET, which is much better than GLAST or air Cherenkov telescopes over 10 GeV, is ideal for detection of gamma-ray lines in the GeV-TeV region from WIMP dark matter annihilations. The high precise observations of electrons(+positrons) also enable us to detect distinctive positron features from WIMP annihilations. In this paper, we present prospects of gamma-ray observations and dark matter search by the hybrid observations of gamma rays and electrons with CALET.