A Positron Production Efficiency Measurement using the IAC’S High Repetition Rate LINAC

Sadiq Setiniyaz
Idaho State University
Department of Physics
Idaho Accelerator Center

The positron production efficiency of a potential Linac based positron source was measured that relies on a quadrupole triplet system to collect positrons. Positrons are produced when a 2mm thick tungsten target is impinged by electrons from the High Repetition Rate Linac (HRRL) at Idaho State University's (ISU) Idaho Accelerator Center (IAC). When a 12 MeV electron beam is used on the tungsten target, positrons escape from the downstream side of the tungsten with a wide momentum and angular spread. Positrons with energies between one to five MeV were observed experimentally after the beam line's 90 degree bend using NaI detectors. Positrons that annihilated on a second tungsten target, located at the end of the 90 degree beamline, produced 511 keV photons that were observed using the NaI detectors. In this talk, the speaker will talk about theory of the positron production as well as the experimental setup, procedure, and results.