Efficiency calibration and coincidence summing correction for a large volume (946cm) LaBr(Ce) detector: GEANT4 simulations and experimental measurements.

The paper describes the studies on efficiency calibration and coincidence summing correction for a 3.5″×6″ cylindrical LaBr(Ce)detector. GEANT4 simulations were made with point sources, namely, Co, Nb, Na, Sc and Na. The simulated efficiencies, extracted using Co, Nb, Na and Sc that emit coincident gamma rays with same decay intensities, were corrected for coincidence summing by applying the method proposed by Vidmar et al. (2003). The method was applied, for the first time, for correcting the simulated efficiencies extracted using Na that emits coincident gamma rays with different decay intensities. The measured results obtained using Co and Na were found to be in good agreement with simulated results.