Search for the rare decays $\pi^+ \to \mu^+\nu_\mu\nu\bar\nu$ and $\pi^+ \to e^+\nu_e\nu\bar\nu$

Bibliographic Details
Title: Search for the rare decays $\pi^+ \to \mu^+\nu_\mu\nu\bar\nu$ and $\pi^+ \to e^+\nu_e\nu\bar\nu$
Authors: Aguilar-Arevalo, A., Aoki, M., Blecher, M., Britton, D. I., Bruch, D. vom, Bryman, D. A., Chen, S., Comfort, J., Cuen-Rochin, S., Doria, L., Gumplinger, P., Hussein, A., Igarashi, Y., Ito, S., Kettell, S., Kurchaninov, L., Littenberg, L. S., Malbrunot, C., Mischke, R. E., Numao, T., Protopopescu, D., Sher, A., Sullivan, T., Vavilo, D., Gorbunov, D., Kalashnikov, D.
Source: Phys. Rev. D 102, 012001 (2020)
Publication Year: 2020
Collection: High Energy Physics - Experiment
High Energy Physics - Phenomenology
Subject Terms: High Energy Physics - Experiment, High Energy Physics - Phenomenology
More Details: The rare pion decays ${\pi}^+{\rightarrow}{\mu}^+{\nu}_{\mu}{\nu}\bar{\nu}$ and ${\pi}^+{\rightarrow}e^+{\nu}_{e}{\nu}\bar{\nu}$ are allowed in the Standard Model but highly suppressed. These decays were searched for using data from the PIENU experiment. A first result for ${\Gamma}({\pi}^+{\rightarrow}{\mu}^+{\nu}_{\mu}{\nu}\bar{\nu})/{\Gamma}({\pi}^+{\rightarrow}{\mu}^+{\nu}_{\mu})<8.6{\times}10^{-6}$, and an improved measurement ${\Gamma}({\pi}^+{\rightarrow}{e}^+{\nu}_{e}{\nu}\bar{\nu})/{\Gamma}({\pi}^+{\rightarrow}{\mu}^+{\nu}_{\mu})<1.6{\times}10^{-7}$ were obtained.
Comment: 6 figures
Document Type: Working Paper
DOI: 10.1103/PhysRevD.102.012001
Access URL: http://arxiv.org/abs/2006.00389
Accession Number: edsarx.2006.00389
Database: arXiv
More Details
DOI:10.1103/PhysRevD.102.012001