Light yield nonproportionality of CsI(Tl), CsI(Na), and YAP

CsI(Tl), CsI(Na), and YAP light yield nonproportionality has been characterized using the Compton Coincidence Technique. Measured electron responses were used to calculate photon responses of the scintillators studied. These calculated photon responses were then compared with measured photon responses. In addition results from electron response measurements and photon response calculations were compared with previously reported results. While the CsI(Na) electron response was observed to have the largest deviation from proportionality (about 40%), YAP was observed to have a nearly proportional response. The CsI(Tl) calculated photon response was observed to agree to within 1% with measured photon response in this study for all measured photon energies. While the CsI(Na) calculated photon response agreed to within 1% of measured data for photon energies above 60 keV, deviations up to 4% were observed below 60 keV.