Maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals estimated from the scintillation model for liquid rare gases

The maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals were estimated theoretically by applying the scintillation model for liquid rare gases to crystal scintillators. Average energies required to produce one scintillation photon in the maximum scintillation yield, Wso, were estimated to be 10.6 ± 0.3 or 11.6 ± 0.3 eV for NaI(Tl) and 11.6 ± 0.3 or 12.5 ± 0.3 eV for CsI(Tl). The new experiment on scintillation yields gives Wso of 10.8 ± 2.0 eV for NaI(Tl) and 11.3 ± 2.1 or 9.3 ± 1.7 eV for CsI(Tl). The values show good agreement with the theoretical estimations. These results demonstrate that the scintillation model in liquid rare gases is applicable to inorganic scintillators such as NaI(Tl) and CsI(Tl) crystals.