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Extra dimensions and invisible decay of orthopositronium

S. N. Gninenko·N. V. Krasnikov·A. Rubbia
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Abstract

We point out that some models with infinite additional dimension(s) of Randall-Sundrum type predict the disappearance of orthopositronium (o-Ps) into additional dimension(s). The experimental signature of this effect is the o-Ps -> invisible decay of orthopositronium which may occur at a rate within three orders of magnitude of the present experimental upper limit. This result enhances existing motivations for a more sensitive search for this decay mode and suggests additional directions for testing extra dimensions in non accelerator experiments.

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S. N. Gninenko, N. V. Krasnikov, A. Rubbia. 2003-02-23. Extra dimensions and invisible decay of orthopositronium. https://doi.org/10.1103/physrevd.67.075012

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