Probing conventional and new physics at the ESS with coherent elastic neutrino-nucleus scattering

TL;DR

This paper assesses the European Spallation Source's potential to advance understanding of Standard Model parameters and explore new physics through future coherent elastic neutrino-nucleus scattering measurements, offering significant sensitivity improvements.

Contribution

It presents a comprehensive analysis of ESS's capabilities to probe SM parameters and new physics scenarios, including sterile neutrinos and generalized interactions, with detailed sensitivity projections.

Findings

ESS can significantly tighten constraints on SM parameters.

Enhanced statistics improve sensitivity to sterile neutrino phenomena.

Potential to establish leading CE$ u$NS constraints globally.

Abstract

We explore the potential of the European Spallation Source (ESS) in probing physics within and beyond the Standard Model (SM), based on future measurements of coherent elastic neutrino-nucleus scattering (CE$\nu$NS). We consider two SM physics cases, namely the weak mixing angle and the nuclear radius. Regarding physics beyond the SM, we focus on neutrino generalized interactions (NGIs) and on various aspects of sterile neutrino and sterile neutral lepton phenomenology. For this, we explore the violation of lepton unitarity, active-sterile oscillations as well as interesting upscattering channels such as the sterile dipole portal and the production of sterile neutral leptons via NGIs. The projected ESS sensitivities are estimated by performing a statistical analysis considering the various CE$\nu$NS detectors and expected backgrounds. We find that the enhanced statistics achievable in view of the highly intense ESS neutrino beam, will offer a drastic improvement in the current constraints obtained from existing CE$\nu$NS measurements. Finally, we discuss how the ESS has the potential to provide the leading CE$\nu$NS-based constraints, complementing also further experimental probes and astrophysical observations.