Evidence for Neutrino Oscillations from Muon Decay at Rest
Abstract
A search for nu_bar_mu to nu_bar_e oscillations has been conducted at the Los Alamos Meson Physics Facility using nu_bar_mu from mu+ decay at rest. The nu_bar_e are detected via the reaction (nu_bar_e,p) -> (e+,n), correlated with the 2.2 MeV gamma from (n,p) -> (d,gamma). The use of tight cuts to identify e+ events with correlated gamma rays yields 22 events with e+ energy between 36 and 60 MeV and only 4.6 (+/- 0.6) background events. The probability that this excess is due entirely to a statistical fluctuation is 4.1E-08. A chi^2 fit to the entire e+ sample results in a total excess of 51.8 (+18.7) (-16.9) (+/- 8.0) events with e+ energy between 20 and 60 MeV. If attributed to nu_bar_mu -> nu_bar_e oscillations, this corresponds to an oscillation probability (averaged over the experimental energy and spatial acceptance) of 0.0031 (+0.0011) (-0.0010) (+/- 0.0005).
Keywords
Cite
@article{arxiv.nucl-ex/9605001,
title = {Evidence for Neutrino Oscillations from Muon Decay at Rest},
author = {C. Athanassopoulos and L. B. Auerbach and R. L. Burman and I. Cohen and D. O. Caldwell and B. D. Dieterle and J. B. Donahue and A. M. Eisner and A. Fazely and F. J. Federspiel and G. T. Garvey and M. Gray and R. M. Gunasingha and R. Imlay and K. Johnston and H. J. Kim and W. C. Louis and R. Majkic and J. Margulies and K. McIlhany and W. Metcalf and G. B. Mills and R. A. Reeder and V. Sandberg and D. Smith and I. Stancu and W. Strossman and R. Tayloe and G. J. VanDalen and W. Vernon and N. Wadia and J. Waltz and Y-X. Wang and D. H. White and D. Works and Y. Xiao and S. Yellin The LSND Collaboration},
journal= {arXiv preprint arXiv:nucl-ex/9605001},
year = {2008}
}
Comments
57 pages, 34 figures, revtex, additional information available at http://nu1.lampf.lanl.gov/~lsnd/