Status of the Experiment on the Laboratory Search for the Electron Antineutrino Magnetic Moment at the Level mu_nu < 3 s 10^{-12}mu_B

TL;DR

This experiment aims to significantly improve the laboratory limit on the electron antineutrino magnetic moment using advanced detectors and a high-activity tritium source, achieving a sensitivity of mu_nu < 3×10^{-12} mu_B within 1-2 years.

Contribution

The paper reports on a novel experimental setup combining new detector technologies and a high-intensity tritium source to lower the neutrino magnetic moment limit by two orders of magnitude.

Findings

Achieved a background level of about 0.1 events/kg keV day.

Utilized silicon cryogenic and high purity germanium detectors with low energy thresholds.

Projected to set a new limit of mu_nu < 3×10^{-12} mu_B after 1-2 years.

Abstract

The experiment on the direct detection of antineutrino-electron scattering with an artificial tritium source allows to lower the present-day laboratory limit for the neutrino magnetic moment by two orders of magnitude. The experiment brings together novel unique technologies in studies of rare processes of neutrino-electron scattering: an artificial source of antineutrinos from tritium decay of 40 MCi activity with the antineutrino flux density ~6 10^{14}cm^{-2} s^{-1}; new types of detectors capable of detecting electrons with energy down to ~10 eV, namely, a silicon cryogenic detector based on the ionization-into-heat conversion effect, a high purity germanium detector with the internal amplification of a signal in the electric field. A compact installation located in a specially equipped laboratory underground <100 m w.e.) will provide favorable background conditions for running the experiment. With the background level about 0.1 events/kg keV day and detector assembly masses 3kg and 5kg for the silicon and germanium ones, respectively, the limit for the electron antineutrino magnetic moment mu_nu < 3 10^{-12}mu_B will be obtained during 1-2 years of data acquisition. Status of the experiment and state-of-the-art are presented.