Measuring the weak mixing angle at SBND

TL;DR

This paper evaluates SBND's potential to measure the weak mixing angle via neutrino-electron scattering, demonstrating it can achieve competitive precision and improve upon current neutrino experiment constraints.

Contribution

It presents a detailed simulation showing SBND's capability to constrain the weak mixing angle with 8% precision, a novel application for this detector.

Findings

SBND can measure the weak mixing angle with 8% precision.

The measurement is competitive with other low-energy experiments.

The study highlights the importance of background rejection and flux normalization.

Abstract

The weak mixing angle provides a sensitive test of the Standard Model. We study SBND's sensitivity to the weak mixing angle using neutrino-electron scattering events. We perform a detailed simulation, paying particular attention to background rejection and estimating the detector response. We find that SBND can provide a reasonable constraint on the weak mixing angle, achieving 8% precision for $10^{21}$ protons on target, assuming an overall flux normalization uncertainty of 10%. This result is superior to those of current neutrino experiments and is relatively competitive with other low-energy measurements.