Doctor of Philosophy (PhD)


Physics and Astronomy

Document Type



The CALorimetric Electron Telescope (CALET) is a multi-instrument high-energy astrophysics observatory deployed to the International Space Station (ISS) in August 2015. The primary instrument is the calorimeter (CAL), which is intended for measurement of the cosmic ray electron flux in the energy range 10 GeV - 20 TeV. The CAL is also sensitive to gamma-rays in the energy range 1 GeV - 10 TeV and protons and nuclei up to PeV energies. Also present on the CALET payload are an Advanced Stellar Compass (ASC) for the fine determination of the pointing direction and the CALET Gamma-ray Burst Monitor (CGBM) for the observation of hard x-ray/soft gamma-ray emission from gamma-ray bursts (GRBs). This work focuses on the capabilities and current results of the CAL for observation of gamma-ray sources in the GeV-energy regime. The methodology for the isolation of a gamma-ray dataset is presented and the resulting efficiencies and instrument response functions (IRFs) are derived from Monte Carlo simulated events. These results are validated by comparison with the first two years of flight data from CALET and the consistency with established measurements from other instruments is shown. Finally, independent CALET observations are presented, with an emphasis on the potential for detection of high-energy electromagnetic emission from transient events, including short and long GRBs, gravitational wave events seen by the LIGO/Virgo observatories, and high-energy astrophysical neutrino observations.



Committee Chair

Cherry, Michael L.