Impact of nuclear effects on the extraction of neutrino oscillation parameters

Abstract

We study the possible impact of nuclear effects and final state interactions on the determination of the oscillation parameters due to mis-reconstruction of non-quasi-elastic events as quasi-elastic events at low energies. We analyze a $ν_μ$ disappearance experiment using a water Čerenkov detector. We find that, if completely ignored in the fit, nuclear effects can induce a significant bias in the determination of atmospheric oscillation parameters, particularly for the atmospheric mixing angle. Even after inclusion of a near detector a bias in the determination of the atmospheric mixing angle comparable to the statistical error remains.

5 pages, 3 figures. Minor changes, references added. Version accepted in Phys. Rev. Lett