Response of parylene-coated NaI(Tl) scintillators at low temperature

Coron, N. ; Cuesta, C. ; García, E. ; Ginestra, C. ; Girard, T.A. ; De Marcillac, P. ; Martínez, M. (Universidad de Zaragoza) ; Ortigoza, Y. ; De Solórzano, A.O. ; Pobes, C. ; Puimedón, J. (Universidad de Zaragoza) ; Redon, T. ; Sarsa, M.L. (Universidad de Zaragoza) ; Torres, L. ; Valko, P. ; Villar, J.A. (Universidad de Zaragoza)

Resumen: Despite that it is widely used as a scintillator at room temperature, the hygroscopicity of NaI complicates its handling and limits its application for many purposes, for example as a cryogenic detector. To overcome this problem we study coating materials that can act as humidity barriers, in particular parylene, a polymer that can be deposited in very radiopure, thin and conformal layers. In this work, several NaI(Tl) samples coated with 2-5 µm parylene-C were tested at low temperature. Luminescence spectra under X-ray excitation are presented at several temperatures as well as the light output vs temperature at 1.5-300 K. Several thermoluminescence peaks were observed at around 60, 95 and 150 K during warm up to room temperature
The mechanical resistance of the coating under thermal cycles was also investigated, and we observed a degradation of the optical appearance and the light output after cooling down to about 100 mK, which compromises the reusability of the samples.

Idioma: Inglés

DOI: 10.1051/epjconf/20136502001

Año: 2014

Publicado en: EPJ web of conferences 65 (2014), [4 pp]
ISSN: 2101-6275

Financiación: info:eu-repo/grantAgreement/ES/MICINN/FPI-CSD2009-00064

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Física Teórica (Dpto. Física Teórica)
Área (Departamento): Área Física Atóm.Molec.y Nucl. (Dpto. Física Teórica)