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arXiv · 1611.03726

Next-to-leading order prediction for the decay $μ\to e \, (e^+e^-) \, ν\barν$

M. Fael·C. Greub
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Abstract

We present the differential decay rates and the branching ratios of the muon decay with internal conversion, $μ\to e \, (e^+e^-) \, ν\barν$, in the Standard Model at next-to-leading order (NLO) in the on-shell scheme. This rare decay mode of the muon is among the main sources of background to the search for $μ\to eee$ decay. We found that in the phase space region where the neutrino energies are small, and the three-electron momenta have a similar signature as in the $μ\to eee$ decay, the NLO corrections decrease the leading-order prediction by about $10-20\%$

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M. Fael, C. Greub. 2017-02-06. Next-to-leading order prediction for the decay $μ\to e \, (e^+e^-) \, ν\barν$. https://doi.org/10.1007/jhep01(2017)084

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