标题： 从静止μ衰变中 neutrino振荡的证据 显示英文标题

标题： Evidence for Neutrino Oscillations from Muon Decay at Rest

摘要： 在洛斯阿拉莫斯介子物理设施中，利用从静止μ+衰变产生的ν̄_μ进行了ν̄_μ到ν̄_e振荡的搜索。 通过反应(ν̄_e,p)→(e+,n)，并结合(n,p)→(d,γ)产生的2.2 MeV伽马射线来检测ν̄_e。使用严格的筛选条件来识别与伽马射线相关的e+事件，得到了22个e+能量在36至60 MeV之间的事件，且只有4.6（±0.6）个背景事件。 这一超额事件完全由统计涨落引起的概率为4.1×10⁻⁸。 对整个e+样本进行χ²拟合，得到e+能量在20至60 MeV范围内的总超额事件为51.8（+18.7）（-16.9）（±8.0）个。 如果归因于ν̄_μ→ν̄_e振荡，则对应的振荡概率（实验能量和空间接受度平均值）为0.0031（+0.0011）（-0.0010）（±0.0005）。 显示英文摘要

摘要： 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).