Characterization of Yb:YAG and Yb:YAP scintillators by means of LAAPD at temperature around 100 K

A new class of scintillators based on charge-transfer luminescence of the Yb3+ ion is being investigated for the last few years. The main prospect for these scintillators is in neutrino physics. The crystals manifest maximum light output at temperatures 100 K<T<150 K. In this range Large Area Avalanche Photodiodes (LAAPD) are the best photodetectors. In this work Yb(25%):YAG and Yb(5%):YAP scintillators were characterized by means of a 16 mm diameter API LAAPD at temperatures around 100 K. Light yield and energy resolution were determined. Light yield non-proportionality was detected for all the crystals comparing light output at 661.6 and 59.6 keV peaks.