Performance characteristics of micro crystal element (MiCE) detectors

Abstract

Two micro crystal element (MICE) detector unit designs are evaluated. The detector units are built using highly packed arrays of 0.8/spl times/0.8/spl times/6 mm mixed lutetium silicate (MLS) crystals. The first detector unit, MiCE1, consists of a 5/spl times/5 array of 0.8 mm/spl times/0.8 mm/spl times/6 mm MLS crystals. The detector unit is coupled to four channels of a Hamamatsu multichannel photomultiplier tube (PMT) via a 2/spl times/2 array of 2 mm/spl times/2 mm square optical fibers. The crystal of interaction is determined using simple Anger style logic. Light is shared within the crystal array to help facilitate decoding of the crystals. A full detector module will consist of a 4/spl times/4 array of detector units coupled to a 64-channel PMT. The second detector unit, MiCE2, consists of an array of 0.8 mm/spl times/0.8 mm/spl times/6 mm MLS crystals directly coupled to a 6+6 cross-anode PMT. The crystal of interaction is determined using simple Anger style logic. In both designs, individual crystals are well visualized. Simulations were performed to determine the imaging characteristics of a detector system consisting of MiCE1 detector modules (12.8-cm ring diameter). Results indicate that a detector system built with the authors' MiCE detectors will have an image resolution of less than 1 mm for the central 2 cm of the field of view.