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New constraints on R-parity violation from μ-e conversion in nuclei

K. Huitu·J. Maalampi·M. Raidal·A. Santamaria
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Abstract

We derive new constraints on the products of explicitly R-parity violating couplings $λ$ and $λ'$ in MSSM from searches for μ-e conversion in nuclei. We concentrate on the loop induced photonic coherent conversion mode. For the combinations $|λλ|$ which in μ-e conversion can be probed only at loop level our constraints are in many cases more stringent than the previous ones due to the enhancement of the process by large $\ln(m^2_f/m^2_{\tilde f}).$ For the combinations of $|λ'λ'|$ the tree-level μ-e conversion constraints are usually more restrictive than the loop ones except for two cases which involve the third generation. With the expected improvements in the experimental sensitivity, the μ-e conversion will become the most stringent test for all the involved combinations of couplings.

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K. Huitu, J. Maalampi, M. Raidal, A. Santamaria. 1997-12-03. New constraints on R-parity violation from μ-e conversion in nuclei. https://doi.org/10.1016/s0370-2693(98)00344-x

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