New constraints on muon-neutrino to electron-neutrino transitions in MINOS

This paper reports results from a search for e transitions by the MINOS experiment based on a 71020 protons-on-target exposure. Our observation of 54 candidate e events in the far detector with a background of 49.17.0(stat)2.7(syst) events predicted by the measurements in the near detector requires 2sin2(213)sin223<0.12(0.20) at the 90% C.L. for the normal (inverted) mass hierarchy at CP=0. The experiment sets the tightest limits to date on the value of 13 for nearly all values of CP for the normal neutrino mass hierarchy and maximal sin2(223).