The Cosmic Ray Energetics And Mass experiment is planned for a launch in 2015 to the International Space Station to investigate high energy cosmic rays. The aim of this mission is to measure high energy cosmic rays composition and extend the highest energies to overlap with the ground experiments. Furthermore, it is to verify excess of the cosmic rays electrons from 300 GeV and above 800 GeV. We have developed the Top Counting Detector and Bottom Counting Detector (T/BCD) for the mission. The T/BCDs configuration provide electron and proton separation by using the different cascade shapes between electromagnetic and hadronic interaction. The T/BCDs provide not only a high energy trigger to backup the calorimeter trigger but also a low energy trigger for the calibration of the charge measurement system. For this purpose, both of the T/BCDs consist of plastic scintillators and two dimensional silicon Photo-Diode array with a readout electronics. The TCD is located between the carbon target and the calorimeter, and the BCD is located below the calorimeter. We successfully had a beam test for feasibility of the T/BCDs at European Organization for Nuclear Research. I designed test electronics of the T/BCDs with an Application Specific Integrated Circuit and a Field Programmable Gate Array with an Ethernet interface. The test electronics components are replaced in the prototype electronics to reduce risks and increase survivability at the launch and operations in the space.
The prototype electronics used radiation hard components as suggested by National Aeronautics and Space Administration. The performance of the prototype electronics was tested with various radiation sources. After the prototype performance test was completed, successfully I designed flight electronics and the sensors with the scintillators were assembled. We have performed environmental tests of the T/BCDs electronics and mechanical components to be qualify in the space and launch environment conditions. I have resolved some problems which were occurred in thermal test. I have measured the characteristics of the T/BCDs electronics and capability of the trigger.
Thesis Advisor: Prof. Hongjoo Kim