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arXiv · 0707.3492

Limit on the electric charge-nonconserving $μ^+ \to invisible$ decay

S. N. Gninenko
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Abstract

The first limit on the branching ratio of the electric charge-nonconserving invisible muon decay $Br(μ^+ \to invisible) < 5.2 \times 10^{-3}$ is obtained from the recently reported results on new determination of the Fermi constant from muon decays. The results of a feasibility study of a new proposed experiment for a sensitive search for this decay mode at the level of a few parts in 10^{11} are presented. Constrains on the $τ\to invisible$ decay rate are discussed. These leptonic charge-nonconserving processes may hold in four-dimensional world in models with infinite extra dimensions, thus making their searches complementary to collider experiments probing new physics.

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S. N. Gninenko. 2007-07-24. Limit on the electric charge-nonconserving $μ^+ \to invisible$ decay. https://doi.org/10.1103/physrevd.76.055004

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