Phenomenological implications of the high-precision COHERENT germanium CE$\nu$NS data

TL;DR

This paper analyzes high-precision germanium CEνNS data from COHERENT, updating constraints on Standard Model parameters, nuclear properties, and beyond Standard Model scenarios using a comprehensive global analysis.

Contribution

It provides the first detailed phenomenological analysis of germanium CEνNS data, refining key physical parameters and exploring new physics implications.

Findings

Updated constraints on the weak mixing angle.

Refined measurements of the neutron RMS radius of germanium.

Robust bounds on neutrino non-standard interactions.

Abstract

This work presents the first comprehensive phenomenological analysis of the newly released Coherent Elastic Neutrino-Nucleus Scattering (CE$\nu$NS) data on germanium, measured by the COHERENT collaboration at the Spallation Neutron Source. Leveraging the unprecedented precision of this dataset, we provide state-of-the-art determinations of key Standard Model and nuclear physics parameters. Specifically, we extract updated constraints on the weak mixing angle, the neutrino charge radii, and we perform a detailed extraction of the neutron root-mean-square radius of germanium nuclei. We also investigate the impact of quenching factor uncertainties by exploring an extended Lindhard framework, and assess their effect on the extraction of nuclear parameters. Additionally, we use these results to evaluate scenarios beyond the Standard Model, placing robust bounds on neutrino non-standard interactions. To maximize the statistical power and robustness of our findings, whenever possible, we perform a global combined analysis incorporating previous COHERENT measurements along with reactor antineutrino data from the CONUS+, TEXONO, and $\nu$GeN experiments as well as dark-matter experiments.