Fabrication and scintillation properties of a flexible optical-guiding crystal scintillator

Scintillation properties of a flexible optical-guiding crystal scintillator with a thallium-doped CsI (Tl:CsI) crystal and borosilicate glass as the core and cladding, respectively, are reported. The as-fabricated optical-guiding crystal scintillator exhibits a light yield of 31,000 photons MeV-1 under 662 keV gamma-ray irradiation. The recrystallized sample is transparent and provides a higher light yield of 54,000 photons MeV-1, which is comparable to that of single-crystal Tl:CsI. The decay times are 400 ns (28%) and 1,350 ns (72%). This material can serve as a scintillator fiber with high sensitivity to gamma- and X-rays, high light yield, and energy discrimination.