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arXiv · 1602.07528

Trilateration-based reconstruction of ortho-positronium decays into three photons with the J-PET detector

A. Gajos·D. Kamińska·E. Czerwiński·D. Alfs·T. Bednarski·P. Białas·B. Głowacz·M. Gorgol·B. Jasińska·Ł. Kapłon·G. Korcyl·P. Kowalski·T. Kozik·W. Krzemień·E. Kubicz·M. Mohammed·Sz. Niedźwiecki·M. Pałka·M. Pawlik-Niedźwiecka·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
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Abstract

This work reports on a new reconstruction algorithm allowing to reconstruct the decays of ortho-positronium atoms into three photons using the places and times of photons recorded in the detector. The method is based on trilateration and allows for a simultaneous reconstruction of both location and time of the decay. Results of resolution tests of the new reconstruction in the J-PET detector based on Monte Carlo simulations are presented, which yield a spatial resolution at the level of 2 cm (FWHM) for X and Y and at the level of 1 cm (FWHM) for Z available with the present resolution of J-PET after application of a kinematic fit. Prospects of employment of this method for studying angular correlations of photons in decays of polarized ortho-positronia for the needs of tests of CP and CPT discrete symmetries are also discussed. The new reconstruction method allows for discrimination of background from random three-photon coincidences as well as for application of a novel method for determination of the linear polarization of ortho-positronium atoms, which is also introduced in this work.

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A. Gajos, D. Kamińska, E. Czerwiński, D. Alfs, T. Bednarski, P. Białas, B. Głowacz, M. Gorgol, B. Jasińska, Ł. Kapłon, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemień, E. Kubicz, M. Mohammed, Sz. Niedźwiecki, M. Pałka, M. Pawlik-Niedźwiecka, 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. 2016-02-24. Trilateration-based reconstruction of ortho-positronium decays into three photons with the J-PET detector. https://doi.org/10.1016/j.nima.2016.02.069

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