Research‎ > ‎


CALET (CALorimetric Electron Telescope)

What is CALET?

The science goal of CALET (CALorimetric Electron Telescope) is to understand the origin of high energy cosmic raysand dark matter through the observations of high energy electrons and gamma-rays from the space.  It is scheduled to be launched on 2015.  It will be attached to the exposed facility of Japanese Experimental Module (JEM) on International Space Station (ISS).  

Science Instruments

Calorimeter (CAL)

CAL is the main instrument of CALET.  CAL will observe electrons, gamma-rays, protons and charged particles coming from space by utilizing its shower imaging capability.    

CALET Gamma-ray Burst Monitor (CGBM)

CGBM consists of two different scintillators to cover a broad spectral range.  The primary target is to study gamma-ray bursts.  AGU (Prof. Yoshida) is the PI institute of CGBM.  

Science Goals
  • Identifying the nearby origin of cosmic-rays
  • Survey of dark matter signature
  • Study of cosmic-ray acceleration
  • Observations of gamma-ray transients

Development of CGBM

CGBM is a hard X-ray/gamma-ray scintillation detector.  Scintillator is a crystal which emits an optical light when it interacts with X-ray/gamma-ray.  It is possible to measure the energy of incoming X-ray/gamma-ray photons by amplifying and converting the emitted lights by a crystal to electrical signal by a photomultiplier tube.  

CGBM uses two types of crystal, LaBr3(Ce) and BGO.  The CGBM which uses a LaBr3(Ce) crystal is called the Hard X-ray Monitor (HXM).  The HXM covers the energy range from 7 keV to 1 MeV and has two identical units.  The CGBM which uses a BGO crystal is called the Soft Gamma-ray Monitor (SGM).  The SGM covers the energy range from 100 keV to 20 MeV.  By combining HXM and SGM, CGBM can cover the board energy range from 7 keV up to 20 MeV.  CGBM is the supporting instrument of CAL's gamma-ray observations.  

Specification of CGBM