The Experimental Study of Lanthanum Bromide Detector in the Gamma Ray Imaging

Abstract

Cerium activated lanthanum bromide (LaBr3:Ce3+) scintillator crystal has shown very promising characteristics for high-resolution and high-sensitivity gamma ray imaging and spectrometric applications [1,2,. In this paper, we present some preliminary results of a compact gamma camera based on LaBr3:Ce3+ crystal. The detector module consists of a continuous LaBr3:Ce3+ crystal with a sensitive area of 50x50 mm2 and 5mm thickness coupling to a Hamamatsu H8500 position-sensitive photomultiplier tube (PSPMT). A compact multiplexed readout based on symmetric charge division circuit (SCD) was developed to reduce the 64 anode signal to 16 readout channels, and a resistive division network to reduce the readout channels from 16 to 4. The performance of the imaging detector module was tested using a 57Co source. The preliminary results showed that this detector module can achieve an effective field-of-view (FOV) of ~39x39 mm2 with a good intrinsic spatial resolution around 1.5mm and energy resolution of 9.2% at 122 keV.