LXXIV International conference Nucleus-2024: Fundamental problems and applications

Search for Sterile Neutrino with the Daya Bay full dataset

3 Jul 2024, 13:00

20m

Second floor Hall (BLTP)

Oral Neutrino physics and nuclear astrophysics

Speaker

Vitalii Zavadskyi (JINR)

Description

on behalf of Daya Bay Collaboration

Modern neutrino physics contains a few anomalies that can not be described by the three-neutrino mixing and oscillation framework. Reactor neutrino experiments observed a deficit of the anti-neutrino flux at $2.5\sigma$ level with respect to the prediction (Huber-Mueller model). Gallium detectors for solar neutrinos observed a deficit of events from radioactive calibration sources of neutrino (${}^{37}$Ar and ${}^{51}$Cr) at $2.3\sigma$ level.
These anomalies could be explained with one or more sterile neutrinos, which interact only gravitationally.
The reactor experiment Daya Bay has stored $5.55\cdot {10}^6$ IBD candidates from the interaction of electron antineutrinos. The statistics have been accumulated on a distance from 400 m to 2 km between reactor and detectors. It makes the experiment sensitive to sterile neutrino in a wide range of sterile mass splittings $\mathrm{\Delta }{m}_{41}^2$.
Since no significant signal of sterile neutrino was observed, it enables us to exclude a large region of sterile neutrino parameter space. The sensitivity to sterile amplitude ${\sin }^{2}2{\theta }_{14}$ achieves $5\cdot {10}^{-3}$ with 95% confidence level in a region of $2\cdot {10}^{-4}$ eV${}^2<\mathrm{\Delta }{m}_{41}^2<2\cdot {10}^{-1}$ eV${}^2$.
The overview of the experiment and results of the analysis of the full dataset of Daya Bay will be presented.

Presentation materials

Zavadskyi_NUCLEUS-2024-07-03_.pdf