Benchmarking NaI(Tl) electron energy resolution measurements

A technique for validating electron energy resolution [[eta].sub.e] results measured using the modified Compton coincidence technique (MCCT) has been developed. This technique relies on comparing measured gamma-ray energy resolution [[eta].sub.[gamma]] with calculated values that were determined using the measured [[eta].sub.e] results. These [[eta].sub.[gamma]] calculations were based on Monte Carlo photon transport simulations, the measured NaI(Tl) electron response, a simplified cascade sequence, and the measured [[eta].sub.e] results. To demonstrate this technique, MCCT-measured NaI(Tl) [[eta].sub.e] results were used along with measured [[eta].sub.[gamma]] results from the same NaI(Tl) crystal. Agreement to within 5% was observed for all energies considered between the calculated and measured [[eta].sub.[gamma]] results for the NaI(Tl) crystal characterized. The calculated [[eta].sub.[gamma]] results were also compared with previously published [[eta].sub.[gamma]] measurements with good agreement (< 10%). In addition to describing the validation technique that was developed in this study and the results, a brief review of the [[eta].sub.e] measurements made using the MCCT is provided. Based on the results of this study, it is believed that the MCCT-measured [[eta].sub.e] results are reliable. Thus, the MCCT and this validation technique can be used in the future to characterize the [[eta].sub.e] of other scintillators and to determine NaI(Tl) intrinsic energy resolution. Index Terms--Electron energy resolution, electron response, light yield nonproportionality.