The partial truncated icosahedron phoswich array for detection of low energy charged pions and light charged particles

The Partial Truncated Icosahedron (ParTI) phoswich array has been designed for the detection of low energy charged pions and other light charged particles for the study of pionic fusion reactions. The array consists of 15 plastic/CsI(Tl) phoswich detector units arranged in approximately one hemisphere of a truncated icosahedron geometry. The phoswich detectors’ particle identification capabilities have been characterized. A pulse shape discrimination technique has demonstrated isotopic identification for Z = 1 and Z = 2 particles and elemental identification up to at least Z = 3. Utilization of digital electronics allows for increased sensitivity in event triggering and independent verification of pion detection. A calibration technique for the array has also been developed.