Performance Characteristics of Continuous Miniature Crystal Element (cMiCE) Detectors

Abstract

In this work, we investigate the performance characteristics of our continuous miniature crystal element detector (cMiCE). Versions with a 25 mm by 25 mm by 4 mm thick LSO crystal and with a 50 mm by 50 mm by 8 mm thick LSYO crystal were evaluated. Both detectors utilized a 64-channel flat panel photomultiplier tube (PMT). The intrinsic spatial resolution for the detectors was evaluated using standard Anger positioning and a statistics based positioning (SBP) algorithm. We also examined the effect different reflective materials applied on the entrance surface had on the intrinsic resolution for the 8 mm LYSO crystal. The average energy resolution was 20% for the 4 mm thick LSO crystal and 16% - 21% for the 8 mm thick LYSO crystal. The average intrinsic spatial resolution for the 4 mm thick crystal was 1.8 mm full width at half maximum (FWHM) for Anger positioning to within 3 mm of the crystal's edge and 1.14 mm FWHM for SBP to within 2 mm of the edge. The average intrinsic spatial resolution for the 8 mm thick crystal was 2.2 mm FWHM for Anger positioning to within 8 mm of the crystal's edge and 1.3-1.5 mm FWHM (depending on the reflective material used) for SBP to within 2 mm of the edge. Intrinsic spatial resolution is reported without correcting for point source size. The point spot flux had a FWHM of -0.52 mm. Using the SBP algorithm showed significant improvement in spatial resolution, linearity of positioning result, and effective field of view for our cMiCE detector