Feasibility study of the time reversal symmetry tests in decays of metastable positronium atoms with the J-PET detector

A. Gajos; C. Curceanu; E. Czerwiński; K. Dulski; M. Gorgol; N. Gupta-Sharma; B. C. Hiesmayr; B. Jasińska; K. Kacprzak; Ł. Kapłon; D. Kisielewska; G. Korcyl; P. Kowalski; T. Kozik; W. Krzemień; E. Kubicz; M. Mohammed; Sz. Niedźwiecki; M. Pałka; M. Pawlik-Niedźwiecka; L. Raczyński; J. Raj; Z. Rudy; S. Sharma; Shivani; R. Shopa; M. Silarski; M. Skurzok; W. Wiślicki; B. Zgardzińska; M. Zieliński; P. Moskal

arXiv · 1804.07148

Feasibility study of the time reversal symmetry tests in decays of metastable positronium atoms with the J-PET detector

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Abstract

This article reports on the feasibility of testing of the symmetry under reversal in time in a purely leptonic system constituted by positronium atoms using the J-PET detector. The present state of T symmetry tests is discussed with an emphasis on the scarcely explored sector of leptonic systems. Two possible strategies of searching for manifestations of T violation in non-vanishing angular correlations of final state observables in the decays of metastable triplet states of positronium available with J-PET are proposed and discussed. Results of a pilot measurement with J-PET and assessment of its performance in reconstruction of three-photon decays are shown along with an analysis of its impact on the sensitivity of the detector for the determination of T -violation sensitive observables.

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A. Gajos, C. Curceanu, E. Czerwiński, K. Dulski, M. Gorgol, N. Gupta-Sharma, B. C. Hiesmayr, B. Jasińska, K. Kacprzak, Ł. Kapłon, D. Kisielewska, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemień, E. Kubicz, M. Mohammed, Sz. Niedźwiecki, M. Pałka, M. Pawlik-Niedźwiecka, L. Raczyński, J. Raj, Z. Rudy, S. Sharma, Shivani, R. Shopa, M. Silarski, M. Skurzok, W. Wiślicki, B. Zgardzińska, M. Zieliński, P. Moskal. 2018-04-19. Feasibility study of the time reversal symmetry tests in decays of metastable positronium atoms with the J-PET detector. https://arxiv.org/abs/1804.07148

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