Comparison of Modeled and Measured Performance of a GSO Crystal as Gamma   Detector
  We have modeled, tested, and installed a large, cerium-activated Gd2SiO5 crystal scintillator for use as a detector of gamma rays. We present the measured detector response to two types of incident photons: nearly monochromatic photons up to 40 MeV, and photons from a continuous Compton backscattering spectrum up to 200 MeV. Our GEANT4 simulations, developed to determine the analyzing power of the Compton polarimeter in Hall A of Jefferson Lab, reproduce the measured spectra well. 
D. S. Parno, M. Friend, V. Mamyan, F. Benmokhtar, A. Camsonne, G. B.   Franklin, K. Paschke, B. Quinn
physics.ins-det