Measuring the Weak Mixing Angle in the DUNE Near Detector Complex

TL;DR

The paper explores how the DUNE near detector can precisely measure the weak mixing angle through neutrino-electron scattering, enhancing understanding of electroweak interactions at low energies.

Contribution

It demonstrates that the DUNE-PRISM detector can significantly improve constraints on the electron's weak couplings and measure the weak mixing angle with about 2% precision after seven years.

Findings

DUNE-PRISM can constrain electron weak couplings effectively.

Measurement of sin^2θ_W with ~2% precision is feasible.

Combining scattering data with neutrino trident production enhances sensitivity.

Abstract

The planned DUNE experiment will have excellent sensitivity to the vector and axial couplings of the electron to the $Z$-boson via precision measurements of neutrino--electron scattering. We investigate the sensitivity of DUNE-PRISM, a movable near detector in the direction perpendicular to the beam line, and find that it will qualitatively impact our ability to constrain the weak couplings of the electron. We translate these neutrino--electron scattering measurements into a determination of the weak mixing angle at low scales and estimate that, with seven years of data taking, the DUNE near-detector can be used to measure $\sin^2\theta_W$ with about 2\% precision. We also discuss the impact of combining neutrino--electron scattering data with neutrino trident production at DUNE-PRISM.