Scintillation Properties and α-ray Detection Capabilities of Thin-film Plastic Scintillators

• Published in: Sensors and materials 2019-01, Vol.31 (4(2)), p.1233
• Main Authors: Koshimizu, Masanori, Yanagida, Takayuki, Kamishima, Ryoji, Fujimoto, Yutaka, Asai, Keisuke
• Format: Article
• Language: English
• Subjects: Absorption; Alpha rays; Decay rate; Dependence; Film thickness; Photoluminescence; Photons; Pulse amplitude; Scintillation; Scintillation counters; Spectra; Thin films
• ISSN: 0914-4935
• DOI: 10.18494/SAM.2019.2182

The photoluminescence and scintillation properties of thin-film plastic scintillators of 5–100 µm thicknesses have been analyzed. The photoluminescence and X-ray-induced radioluminescence spectra exhibited a peak at 400–450 nm, which is typical for generic plastic scintillators. As for the radioluminescence spectra, the contribution of the short-wavelength component decreased with the increase in thickness owing to the self-absorption of scintillation photons inside the scintillators themselves. The temporal profiles of scintillation exhibited a fast decay on the order of nanoseconds. The pulse-height spectra of the scintillation detectors equipped with thin-film plastic scintillators were obtained for 5.4 MeV α-rays from 241Am to evaluate the α-ray detection capabilities. Peaks were observed for thin-film plastic scintillators of 9 and 22 µm thicknesses, and their light yields were estimated to be 830 and 410 photons/MeV, respectively. The dependence of pulse height spectra on film thickness indicates that self-absorption occurs in such thin films.