Evaluation of Quenching Factor in Ce³⁺-Doped Y₂SiO₅ Nanoscintillators for α and γ Radiation Detection

Abstract

Abstract: The quenching factor (QF), defined as the α/γ light output ratio, is a key parameter for evaluating the radiation discrimination performance of scintillators. In this study, five sample detectors were fabricated using Y₂SiO₅:Ce³⁺ nanophosphor powders synthesized at different annealing temperatures of the xerogels, specifically 900 °C, 950 °C, 1000 °C, 1050 °C, and 1250 °C. The detectors were tested under excitation by α-particles (from ²⁴¹Am, 5.48 MeV) and γ-rays (from ¹³⁷Cs, 662 keV). The QF was determined from pulse-height spectra by comparing the relative peak positions corresponding to α and γ interactions. A QF value of 0.46 was obtained for the YSO_1250 sample, indicating a significant reduction in quenching at higher annealing temperatures. Conversely, samples treated at lower temperatures exhibited stronger quenching, with QF values as low as 0.17. This trend is attributed to improved crystallinity and reduced defect density at elevated temperatures, which enhance scintillation efficiency for highly ionizing α-particles. These findings demonstrate that annealing temperature serves as an effective tuning parameter for optimizing the QF and, consequently, the scintillator's suitability for either α/γ discrimination or α-sensitivity, depending on the application.