Development of fiber-optic radiation sensor for gamma-ray spectroscopy: comparative study on efficiency of LYSO:Ce, YSO:Ce, and BGO scintillation crystals

In this study, we fabricated a fiber-optic radiation sensor using three kinds of inorganic scintillation crystals with the same dimension, such as LYSO:Ce, YSO:Ce, and BGO. Gamma-ray energy spectra for Cs-137 were measured with three kinds of inorganic scintillators to select an optimum scintillator that is suitable to use for gamma-ray energy spectroscopy. The total counts of the scintillating lights, were also obtained according to the activity of Cs-137. As a result, the energy spectra measured using the three scintillators were clearly different, thereby they showed clear distinction about the energy resolution and position of the inherent photopeak of Cs-137. Although all scintillators had a linear response over the activity of Cs-137, we selected LYSO:Ce as an optimum scintillator because it provided good energy resolution and the highest light output in our experimental setup.