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arXiv · hep-ph/9505443

THE ORTHOPOSITRONIUM DECAY PUZZLE AND PRIMORDIAL NUCLEOSYNTHESIS

R. Escribano·E. Masso·R. Toldra
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Abstract

The discrepancy between the experimental decay rate of orthopositronium (o-Ps) and the QED theoretical prediction can be solved by invoking decays of o-Ps into exotic particles with branching ratios of the order of 10^{-3}. We show that considerations based on primordial nucleosynthesis and effective Lagrangians place a very stringent upper bound: B = Gamma(o-Ps -> ``exotic'' + ...)/Gamma(o-Ps) <= 2 x 10^{-15}, ruling out the exotic decay solution to the puzzle.

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R. Escribano, E. Masso, R. Toldra. 1995-05-31. THE ORTHOPOSITRONIUM DECAY PUZZLE AND PRIMORDIAL NUCLEOSYNTHESIS. https://doi.org/10.1016/0370-2693(95)00797-o

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