{"paper":{"title":"PALS investigations of free volumes thermal expansion of J-PET plastic scintillator synthesized in polystyrene matrix","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["nucl-ex"],"primary_cat":"physics.ins-det","authors_text":"A. Gajos, A. Kochanowski, A. S{\\l}omski, A. Strzelecki, A. Wieczorek, B. Jasi\\'nska, B. Zgardzi\\'nska, D. Kami\\'nska, E. Czerwi\\'nski, E. Kubicz, G. Korcyl, {\\L}. Kap{\\l}on, L. Raczy\\'nski, M. Gorgol, M. Pa{\\l}ka, M. Silarski, M. Zieli\\'nski, N.G. Sharma, O. Rundel, P. Bia{\\l}as, P. Kowalski, P. Moskal, S. Nied\\'zwiecki, T. Bednarski, T. Kozik, W. Krzemie\\'n, W. Wi\\'slicki, Z. Rudy","submitted_at":"2015-08-27T12:01:34Z","abstract_excerpt":"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."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1508.06820","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}