Improved Search for Heavy Neutrinos and a Test of Lepton Universality in the Decay $\pi^+ \rightarrow \mbox{e}^+ \nu$

R. E. Mischke; 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; T. Numao; D. Protopopescu; A. Sher; T. Sullivan; D. Vavilov

arXiv · 1809.10314

Improved Search for Heavy Neutrinos and a Test of Lepton Universality in the Decay $\pi^+ \rightarrow \mbox{e}^+ \nu$

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Abstract

Two results from the PIENU Experiment are presented reporting a test of lepton universality in pion decay and improved limits on heavy neutrinos coupling to positrons. The status of the full analysis for the $\pi^+ \rightarrow \mbox{e}^+ \nu$ branching ratio measurement is summarized.

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R. E. Mischke, 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, T. Numao, D. Protopopescu, A. Sher, T. Sullivan, D. Vavilov. 2018-09-27. Improved Search for Heavy Neutrinos and a Test of Lepton Universality in the Decay $\pi^+ \rightarrow \mbox{e}^+ \nu$. https://arxiv.org/abs/1809.10314

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