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arXiv · 2002.09170

Improved search for two body muon decay ${\mu}^+{\rightarrow}e^+X_H$

A. Aguilar-Arevalo·M. Aoki·M. Blecher·D. I. Britton·D. vom Bruch·D. A. Bryman·S. Chen·J. Comfort·S. Cuen-Rochin·L. Doria·P. Gumplinger·A. Hussein·Y. Igarashi·S. Ito·S. Kettell·L. Kurchaninov·L. S. Littenberg·C. Malbrunot·R. E. Mischke·T. Numao·D. Protopopescu·A. Sher·T. Sullivan·D. Vavilov
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Abstract

Charged lepton flavor violating muon decay ${\mu}^+{\rightarrow}e^+X_H$, where $X_H$ is a massive neutral boson, was sought by searching for extra peaks in the muon decay ${\mu}^+{\rightarrow}e^+{\nu}\bar{\nu}$ energy spectrum in the $m_{X_H}$ mass region $47.8-95.1$ MeV/$c^2$. No signal was found and 90% confidence level upper limits were set on the branching ratio ${\Gamma}({\mu}^+{\rightarrow}e^+X_H)/{\Gamma}({\mu}^+{\rightarrow}e^+{\nu}\bar{\nu})$ at the level of $10^{-5}$ for this region.

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A. Aguilar-Arevalo, M. Aoki, M. Blecher, D. I. Britton, D. vom Bruch, D. A. Bryman, S. Chen, J. Comfort, S. Cuen-Rochin, L. Doria, P. Gumplinger, A. Hussein, Y. Igarashi, S. Ito, S. Kettell, L. Kurchaninov, L. S. Littenberg, C. Malbrunot, R. E. Mischke, T. Numao, D. Protopopescu, A. Sher, T. Sullivan, D. Vavilov. 2020-02-21. Improved search for two body muon decay ${\mu}^+{\rightarrow}e^+X_H$. https://doi.org/10.1103/physrevd.101.052014

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