Recent results of the DANSS experiment

TL;DR

The DANSS experiment analyzed a large dataset of inverse beta decay events to search for sterile neutrinos, finding no significant oscillation signals and constraining the parameter space.

Contribution

This work provides new, more extensive results on sterile neutrino searches using the DANSS detector, improving previous limits with a larger data sample and a robust spectral ratio method.

Findings

No statistically significant sterile neutrino oscillations detected.

Excluded large regions of sterile neutrino parameter space.

Results are preliminary and based on 2.5 times more data than previous analysis.

Abstract

We present new results of the DANSS experiment on the searches for sterile neutrinos. They are based on 2.1 million of inverse beta decay events collected at 10.7, 11.7 and 12.7 meters from the reactor core of the 3.1 GW Kalinin Nuclear Power Plant in Russia. This data sample is 2.5 times larger than the data sample in the previous DANSS publication. The search for the sterile neutrinos is performed using the ratio of $\bar\nu_e$ spectra at two distances. This method is very robust against systematic uncertainties in the $\bar\nu_e$ spectrum and the detector efficiency. We do not see any statistically significant sign for the $\bar\nu_e$ oscillations. This allows us to exclude further a large and interesting part of the sterile neutrino parameter space. All results are preliminary.