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arXiv · 1803.05744

First search for invisible decays of ortho-positronium confined in a vacuum cavity

C. Vigo·L. Gerchow·L. Liszkay·A. Rubbia·P. Crivelli
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Abstract

The experimental setup and results of the first search for invisible decays of ortho-positronium (o-Ps) confined in a vacuum cavity are reported. No evidence of invisible decays at a level $\text{Br}\left(\text{o-Ps}\to\text{invisible}\right) < 5.9\times 10^{-4}$ (90% C. L.) was found. This decay channel is predicted in Hidden Sector models such as the Mirror Matter (MM), which could be a candidate for Dark Matter. Analyzed within the MM context, this result provides an upper limit on the kinetic mixing strength between ordinary and mirror photons of $\epsilon < 3.1 \times 10^{-7}$ (90% C. L.). This limit was obtained for the first time in vacuum free of systematic effects due to collisions with matter.

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C. Vigo, L. Gerchow, L. Liszkay, A. Rubbia, P. Crivelli. 2018-03-15. First search for invisible decays of ortho-positronium confined in a vacuum cavity. https://doi.org/10.1103/physrevd.97.092008

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