Efficiency Calibration of CeBr 3 Scintillator: Simulations and Measurements

In the present work, we have carried out realistic Monte Carlo simulations of the response of a 1" X 1" CeBr
₃
scintillation detector using mono energetic gamma emitter
¹³⁷
Cs and double-gamma emitter
⁶⁰
Co. These simulations were done using GEANT4 toolkit that include radioactive decay module, low energy EM package and general particle source (GPS) module. Apparent efficiencies (both total detection and full energy absorption) so obtained for
⁶⁰
Co have been corrected for coincidence summing using the method proposed by Vidmar et al. [6]. The simulations have also been carried out for the same energies assuming mono-energetic point sources, for comparison. Experimental measurements have also been carried out using calibrated point sources of
¹³⁷
Cs and
⁶⁰
Co. The simulated and the experimental results are found to be in good agreement. This demonstrates the reliability of the correction method, originally proposed for HPGe detector, for efficiency calibration of CeBr
₃
detector.