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arXiv · 1611.07645

Positronium Decay into a Photon and Neutrinos

Andrzej Pokraka·Andrzej Czarnecki
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Abstract

We determine the rates and energy and angular distributions of the positronium decays into a photon and a neutrino-antineutrino pair, Ps-->gamma+nu+anti-nu. We find that both positronium spin states have access to this decay channel, contrary to a previously published result. The low-energy tails of the spectra are shown to be sensitive to the binding effects and agree with Low's theorem. Additionally, we find a connection between the behaviour of the soft photon spectrum in both o-Ps-->gamma+nu+anti-nu and o-Ps-->3gamma decays, and the Stark effect.

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Andrzej Pokraka, Andrzej Czarnecki. 2016-11-23. Positronium Decay into a Photon and Neutrinos. https://doi.org/10.1103/physrevd.94.113012

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