Characterization of solar X-ray response data from the REXIS instrument

Abstract

The REgolith X-ray Imaging Spectrometer (REXIS) is a student-built instrument that was flown on NASA's Origins, Spectral Interpretation, Resource Identification, Safety, Regolith Explorer (OSIRIS-REx) mission. During the primary science observation phase, the REXIS Solar X-ray Monitor (SXM) experienced a lower than anticipated solar x-ray count rate. Solar x-ray count decreased most prominently in the low energy region of instrument detection, and made calibrating the REXIS main spectrometer difficult. This thesis documents a root cause investigation into the cause of the low x-ray count anomaly in the SXM. Vulnerable electronic components are identified, and recommendations for hardware improvements are made to better facilitate future low-cost, high-risk instrumentation. A CAST Analysis is conducted and programmatic recommendations for future student instruments are provided.