Tau neutrino as a probe of nonstandard interaction

Abstract

We study the $\Delta$-resonance and deep inelastic scattering contributions in the tau-neutrino nucleon scattering $\nu_{\tau}+ N \to \tau^- + X$ and $\bar{\nu}_{\tau}+ N \to \tau^+ + X$ in the presence of a charged Higgs and a $W'$ gauge boson. The new physics effects to the quasielastic process have been discussed in a previous work. The extractions of the atmospheric mixing angle $\theta_{23}$ rely on the standard model cross sections for $\nu_{\tau}+ N \to \tau^- + X$ in $\nu_{\tau}$ appearance experiments. Corrections to the cross sections from the charged Higgs and $W'$ contributions modify the measured mixing angle. We include form factor effects in the new physics calculations and find the deviations of the mixing angle. If high-energy Long Base Line experiments are designed to measure $\theta_{13}$ through tau neutrino appearance, the new physics effects to $\nu_{\tau}+ N \to \tau^- + X$ and $\bar{\nu}_{\tau}+ N \to \tau^+ + X$ can impact the extraction of this mixing angle. Finally, we investigate the new physics effects on the polarization of the $\tau^\mp$ leptons produced in $\nu_\tau (\bar{\nu}_\tau)$ nucleon scattering.