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arXiv · 1508.06820

PALS investigations of free volumes thermal expansion of J-PET plastic scintillator synthesized in polystyrene matrix

A. Wieczorek·B. Zgardzińska·B. Jasińska·M. Gorgol·T. Bednarski·P. Białas·E. Czerwiński·A. Gajos·D. Kamińska·Ł. Kapłon·A. Kochanowski·G. Korcyl·P. Kowalski·T. Kozik·W. Krzemień·E. Kubicz·S. Niedźwiecki·M. Pałka·L. Raczyński·Z. Rudy·O. Rundel·N. G. Sharma·M. Silarski·A. Słomski·A. Strzelecki·W. Wiślicki·M. Zieliński·P. Moskal
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Abstract

The polystyrene dopped with 2,5-diphenyloxazole as a primary fluor and 2-(4-styrylphenyl)benzoxazole as a wavelength shifter, prepared as a plastic scintillator was investigated using positronium probe in wide range of temperatures from 123 to 423 K. Three structural transitions at 260 K, 283 K and 370 K were found in the material. In the o-Ps intensity dependence on temperature, the significant hysteresis is observed. Heated to 370 K, the material exhibits the o-Ps intensity variations in time.

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A. Wieczorek, B. Zgardzińska, B. Jasińska, M. Gorgol, T. Bednarski, P. Białas, E. Czerwiński, A. Gajos, D. Kamińska, Ł. Kapłon, A. Kochanowski, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemień, E. Kubicz, S. Niedźwiecki, M. Pałka, L. Raczyński, Z. Rudy, O. Rundel, N. G. Sharma, M. Silarski, A. Słomski, A. Strzelecki, W. Wiślicki, M. Zieliński, P. Moskal. 2015-08-27. PALS investigations of free volumes thermal expansion of J-PET plastic scintillator synthesized in polystyrene matrix. https://doi.org/10.1515/nuka-2015-0140

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