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arXiv · 2202.04886

New-physics signatures via $C\!P$ violation in $η^{(\prime)}\toπ^0μ^+μ^-$ and $η^\prime\toημ^+μ^-$ decays

Rafel Escribano·Emilio Royo·Pablo Sanchez-Puertas
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Abstract

In this work we investigate the prospect of observing new-physics signatures via $C\!P$ violation in $η^{(\prime)}\toπ^0μ^+μ^-$ and $η^\prime\toημ^+μ^-$ decays at the REDTOP experiment. We make use of the SMEFT to parametrise the new-physics $C\!P$-violating effects and find that the projected REDTOP statistics are not competitive with respect to nEDM experiments. This reasserts the $η\toμ^+μ^-$ process as the most promising channel to find $C\!P$-violation at this experimental facility.

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Rafel Escribano, Emilio Royo, Pablo Sanchez-Puertas. 2022-05-24. New-physics signatures via $C\!P$ violation in $η^{(\prime)}\toπ^0μ^+μ^-$ and $η^\prime\toημ^+μ^-$ decays. https://doi.org/10.1007/jhep05(2022)147

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