First results of the nuGeN experiment on coherent elastic neutrino-nucleus scattering

TL;DR

The nuGeN experiment investigates coherent elastic neutrino-nucleus scattering using reactor antineutrinos and germanium detectors, setting an upper limit on the quenching parameter without detecting a positive signal.

Contribution

First experimental results from nuGeN using reactor antineutrinos to search for coherent elastic neutrino-nucleus scattering with germanium detectors.

Findings

No significant difference between reactor ON and OFF spectra.

Set an upper limit on the quenching parameter k < 0.26 at 90% C.L.

Demonstrated the experimental setup's capability to probe neutrino interactions.

Abstract

The nuGeN experiment is aimed to investigate neutrino properties using antineutrinos from the reactor of the Kalinin Nuclear Power Plant. The experimental setup is located at about 11 meters from the center of the 3.1 GWth reactor core. Scattering of the antineutrinos from the reactor is detected with low energy threshold high purity germanium detector. Passive and active shieldings are used to suppress all kinds of backgrounds coming from surrounding materials and cosmic radiation. The description of the experimental setup together with the first results is presented. The data taken in regimes with reactor ON (94.50 days) and reactor OFF (47.09 days) have been compared. No significant difference between spectra of two data sets is observed, i.e. no positive signals for coherent elastic neutrino-nucleus scattering are detected. Under Standard Model assumptions about coherent neutrino scattering an upper limit on a quenching parameter k < 0.26 (90 \% C.L.) in germanium has been set.