First MINOS Results from the NuMI Beam

Abstract

As of December 2005, the MINOS long-baseline neutrino oscillation experiment collected data with an exposure of $0.93\times10^{20}$ protons on target. Preliminary analysis of these data reveals a result inconsistent with a no-oscillation hypothesis at level of 5.8 sigma. The data are consistent with neutrino oscillations reported by Super-Kamiokande and K2K, with best fit parameters of $\Delta m^2_{23} = 3.05^{+0.60}_{-0.55}\times 10^-3$ and $\sin^22\theta_{23} = 0.88^{+0.12}_{-0.15}$.