Title :
A ring Compton scatter camera for imaging medium energy gamma rays
Author :
Martin, J.B. ; Knoll, G.F. ; Wehe, D.K. ; Dogan, N. ; Jordanov, V. ; Petrick, N. ; Singh, M.
Author_Institution :
Dept. of Nucl. Eng., Michigan Univ., Ann Arbor, MI, USA
fDate :
8/1/1993 12:00:00 AM
Abstract :
The characteristics of a new ring Compton scatter camera are described. This camera is designed to image medium energy (0.5 to 3 MeV) gamma-ray fields. It consists of two positron sensitive detector arrays, i.e. a 4×4 planar array of high purity germanium (HPGe) crystals and a ring array of up to 64 NaI(Tl) crystals. Past evaluations of Compton cameras have employed a planar second detector, which is subjected to a large flux of gamma rays that either pass directly through or undergo small angle scatter in the first detector. A ring array significantly reduces direct and small angle scattered events in the second detector. An analytical model for ring camera systems is developed to predict angular resolution and efficiency, and is benchmarked against measurements made with a prototype system consisting of the 4×4 HPGe array and an eight-element ring. Predictions are made for a system with 64 crystals in the second detector ring
Keywords :
Compton effect; biomedical equipment; cameras; gamma-ray apparatus; gamma-ray detection and measurement; position sensitive particle detectors; radioisotope scanning and imaging; scintillation counters; semiconductor counters; γ rays imaging; 0.5 to 3.0 MeV; Ge; HPGe; NaI(Tl) crystals; NaI:Tl; analytical model; angular resolution; efficiency; eight-element ring; gamma-ray fields; high purity; medium energy gamma rays; planar array; planar second detector; positron sensitive detector arrays; prototype system; ring Compton scatter camera; ring array; small angle scatter; Cameras; Crystals; Gamma ray detection; Gamma ray detectors; Gamma rays; Optical imaging; Planar arrays; Positrons; Scattering; Sensor arrays;
Journal_Title :
Nuclear Science, IEEE Transactions on
