Effects of ${\hbox {Na}}^ + $ , ${\hbox {Mg}}^{2+} $ , ${\hbox {Ca}}^{2+} $ , ${\hbox {Sr}}^{2 +} $ and ${\hbox {Ba}}^{2 +} $ Doping on the Scintillation Properties of ${\hbox {CeBr}}_3$

The effects of ${\hbox {Na}}^ + $ , ${\hbox {Mg}}^{2 +} $ , ${\hbox {Ca}}^{2 +} $ , ${\hbox {Sr}}^{2 +} $ and ${\hbox {Ba}}^{2 +} $ doping on the scintillation properties of ${\hbox {CeBr}}_3$ are evaluated in this paper. ${\hbox {Ca}}^{2 +} $ and ${\hbox {Sr}}^{2 +} $ doped ${\hbox {CeBr}}_3$ show different scintillation properties as compared to undoped ${\hbox {CeBr}}_3$ , i.e. an additional perturbed ${\hbox {Ce}}^{3 +} $ site with emission maxima red-shifted by 30 nm compared to unperturbed ${\hbox {Ce}}^{3 +} $ sites as evidenced by X-ray excited emission and photoluminescence measurements. Also a nearly constant light yield at temperatures below 300 K, an increased decay time and the appearance of multiple glow peaks in thermoluminescence measurements are observed for Ca and Sr doped ${\hbox {CeBr}}_3$ . These effects on the scintillation properties of ${\hbox {CeBr}}_3$ are explained using a single trap model where Br vacancies, formed as charge compensation for the aliovalent dopants, act as electron traps.