Simulation Studies of the CALET Performance
Abstract
The Calorimetric Electron Telescope (CALET) mission aims at revealing unsolved problems in high energy phenomena of the Universe by carrying out a precise measurement of high energy cosmic rays on-board the Japanese Experiment Module Exposed Facility of the International Space Station (ISS). CALET is designed to perform direct measurements of electrons from 1GeV to 10TeV, gamma-rays from 10GeV to a few TeV and nuclei from 10GeV to 1000TeV. The detector consists of Silicon Pixel Array (SIA), Imaging Calorimeter (IMC) and Total Absorption Calorimeter (TASC) to detect the various kinds of particles in very wide energy range. SIA has superior charge resolution of 0.1 e for protons and 0.35 e for irons. IMC composed of scintillating fiber of 1mm square in cross-section and tungsten plates provides the precisely shower profile. TASC composed of PWO scintillator determines the total energy of the incident particle, and separates electrons and gamma-rays from background hadrons. The total absorber is 31 radiation lengths for electromagnetic particles and 1.4 interaction mean free paths for protons. To optimize and evaluate the CALET performance, we have carrying out Monte Carlo simulation study by EPICS code. We obtained following performance for high energy electrons over 100GeV, which is a main target of the CALET mission. The geometrical factor is 1200 cm2sr. The energy resolution is better than a few %. Proton rejection power is 2.0x105. In this poster, we present thus obtained performance in observing each kind of particles. In addition, we will present the trigger system optimized for each kind of particles and expected trigger rate in ISS orbit as well.
- Publication:
-
AAS/High Energy Astrophysics Division #11
- Pub Date:
- March 2010
- Bibcode:
- 2010HEAD...11.3605A