Determination of the 3γfraction from positron annihilation in mesoporous materials for symmetry violation experiment with J-PET scanner

B. Jasińska; M. Gorgol; M. Wiertel; R. Zaleski; D. Alfs; T. Bednarski; P. Białas; E. Czerwiński; K. Dulski; A. Gajos; B. Głowacz; D. Kamińska; Ł. Kapłon; G. Korcyl; P. Kowalski; T. Kozik; W. Krzemień; E. Kubicz; M. Mohammed; Sz. Niedźwiecki; M. Pałka; L. Raczyński; Z. Rudy; O. Rundel; N. G. Sharma; M. Silarski; A. Słomski; A. Strzelecki; A. Wieczorek; W. Wiślicki; B. Zgardzińska; M. Zieliński; P. Moskal

doi:10.5506/aphyspolb.47.453

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arXiv · 1602.05376

Determination of the 3γfraction from positron annihilation in mesoporous materials for symmetry violation experiment with J-PET scanner

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Abstract

Various mesoporous materials were investigated to choose the best material for experiments requiring high yield of long-lived positronium. We found that the fraction of 3γannihilation determined using γ-ray energy spectra and positron annihilation lifetime spectra (PAL) changed from 20% to 25%. The 3gamma fraction and o-Ps formation probability in the polymer XAD-4 is found to be the largest. Elemental analysis performed using scanning electron microscop (SEM) equipped with energy-dispersive X-ray spectroscop EDS show high purity of the investigated materials.

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B. Jasińska, M. Gorgol, M. Wiertel, R. Zaleski, D. Alfs, T. Bednarski, P. Białas, E. Czerwiński, K. Dulski, A. Gajos, B. Głowacz, D. Kamińska, Ł. Kapłon, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemień, E. Kubicz, M. Mohammed, Sz. Niedźwiecki, M. Pałka, L. Raczyński, Z. Rudy, O. Rundel, N. G. Sharma, M. Silarski, A. Słomski, A. Strzelecki, A. Wieczorek, W. Wiślicki, B. Zgardzińska, M. Zieliński, P. Moskal. 2016-02-17. Determination of the 3γfraction from positron annihilation in mesoporous materials for symmetry violation experiment with J-PET scanner. https://doi.org/10.5506/aphyspolb.47.453

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