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arXiv · 1303.0596

Limits on Lepton Flavor Violation from μ-e-conversion

Marcela Gonzalez·Thomas Gutsche·Juan Carlos Helo·Sergey Kovalenko·Valery E. Lyubovitskij·Ivan Schmidt
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Abstract

We revisit the status of Lepton Flavor Violating (LFV) μe qq contact interactions from the view point of μ- e -conversion in nuclei. We consider their contribution to this LFV process via the two mechanisms on the hadronic level: direct nucleon and meson exchange ones. In the former case the quarks are embedded directly into the nucleons while in the latter in mesons which then interact with nucleons in a nucleus. We revise and in some cases reevaluate the hadronic parameters relevant for both mechanisms and calculate the contribution of the above mentioned contact interactions in coherent μ- e -conversion in various nuclei. Then we update the existing upper bounds and also derive new ones for the scales of the μe qq contact interactions from the experimental limits on the capture rates of μ- e -conversion. We compare these limits with the ones derived in the literature from other LFV processes and comment on the prospects of LHC searches related to the contact μe qq interactions.

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Marcela Gonzalez, Thomas Gutsche, Juan Carlos Helo, Sergey Kovalenko, Valery E. Lyubovitskij, Ivan Schmidt. 2013-03-24. Limits on Lepton Flavor Violation from μ-e-conversion. https://doi.org/10.1103/physrevd.87.096020

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