Limits on $ν_μ(\barν_μ)\toν_τ(\barν_τ)$ and $ν_μ(\barν_μ)\toν_e(\barν_e)$ Oscillations from a Precision Measurement of Neutrino-Nucleon Neutral Current Interactions

Abstract

We present limits on $ν_μ(\barν_μ)\toν_τ(\barν_τ)$ and $ν_μ(\barν_μ)\toν_e(\barν_e)$ oscillations based on a study of inclusive $νN$ interactions performed using the CCFR massive coarse grained detector in the FNAL Tevatron Quadrupole Triplet neutrino beam. The sensitivity to oscillations is from the difference in the longitudinal energy deposition pattern of $ν_μN$ versus $ν_τN$ or $ν_e N$ charged current interactions. The $ν_μ$ energies ranged from 30 to 500 GeV with a mean of 140 GeV. The minimum and maximum $ν_μ$ flight lengths are 0.9 km and 1.4 km respectively. For $ν_μ\toν_τ$ oscillations, the lowest 90% confidence upper limit in $\sin^22α$ of $2.7\times 10^{-3}$ is obtained at $Δm^2\sim50$~eV$^2$. This result is the most stringent limit to date for $25<Δm^2<90$ eV$^2$. For $ν_μ\toν_e$ oscillations, the lowest 90% confidence upper limit in $\sin^22α$ of $1.9\times 10^{-3}$ is obtained at $Δm^2\sim350$~eV$^2$. This result is the most stringent limit to date for $250<Δm^2<450$ eV$^2$, and also excludes at 90% confidence much of the high $Δm^2$ region favored by the recent LSND observation.