Observation of Coherent Elastic Neutrino-Nucleus Scattering

TL;DR

This paper reports the first observation of coherent elastic neutrino-nucleus scattering at a 6.7-sigma confidence level using a CsI[Na] detector exposed to SNS neutrinos, confirming Standard Model predictions and constraining new physics.

Contribution

It is the first experimental detection of coherent elastic neutrino-nucleus scattering, demonstrating its feasibility and opening new avenues for neutrino research and applications.

Findings

Detection at 6.7-sigma confidence level

Observation of predicted energy and time signatures

Improved constraints on non-standard neutrino interactions

Abstract

The coherent elastic scattering of neutrinos off nuclei has eluded detection for four decades, even though its predicted cross-section is the largest by far of all low-energy neutrino couplings. This mode of interaction provides new opportunities to study neutrino properties, and leads to a miniaturization of detector size, with potential technological applications. We observe this process at a 6.7-sigma confidence level, using a low-background, 14.6-kg CsI[Na] scintillator exposed to the neutrino emissions from the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. Characteristic signatures in energy and time, predicted by the Standard Model for this process, are observed in high signal-to-background conditions. Improved constraints on non-standard neutrino interactions with quarks are derived from this initial dataset.