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arXiv · 1106.4055

Search for Massive Neutrinos in the Decay pi --> e nu

PIENU Collaboration·M. Aoki·M. Blecher·D. A. Bryman·S. Chen·M. Ding·L. Doria·P. Gumplinger·C. Hurst·A. Hussein·Y. Igarashi·N. Ito·S. H. Kettell·L. Kurchaninov·L. Littenberg·C. Malbrunot·T. Numao·R. Poutissou·A. Sher·T. Sullivan·K. Yamada·M. Yoshida·D. Vavilov
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Abstract

Evidence of massive neutrinos in the pi --> e nu decay spectrum was sought with the background pi --> mu --> e decay chain highly suppressed. Upper limits (90% C.L.) on the neutrino mixing matrix element |U_ei|^2 in the neutrino mass region 60--129 MeV/c^2 were set at the level of 10^-8.

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PIENU Collaboration, M. Aoki, M. Blecher, D. A. Bryman, S. Chen, M. Ding, L. Doria, P. Gumplinger, C. Hurst, A. Hussein, Y. Igarashi, N. Ito, S. H. Kettell, L. Kurchaninov, L. Littenberg, C. Malbrunot, T. Numao, R. Poutissou, A. Sher, T. Sullivan, K. Yamada, M. Yoshida, D. Vavilov. 2011-06-20. Search for Massive Neutrinos in the Decay pi --> e nu. https://doi.org/10.1103/physrevd.84.052002

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