Speaker
Description
The capability to perform precision measurements of nuclear form factors or coupling constants with CEvNS relies on precise knowledge of the incoming neutrino flux and energy spectrum. Isotopes decaying via electron capture (EC) represent a close-to-ideal neutrino source, thanks to the monoenergetic spectrum and the possibility of precisely measuring the source activity. However, the low energy of emitted neutrinos would require detectors with a trigger threshold at the eV level.
Lithium is the only target material that could practically be used to detect EC neutrinos, at the cost of a poor event rate due to the low neutron content. First, lithium’s low nuclear mass would relax the threshold requirement up to 50 eV. Second, several lithium-containing crystals are commercially available and could be used as bolometers. Third, lithium can easily be enriched to 99% in 6Li or 7Li, allowing to perform a differential measurement of the neutrino flux and to disentangle the vector and axial-vector components of CEvNS.
A serendipitous byproduct of a bolometric CEvNS measurement with an EC source is the possibility to perform a truly independent test of the Gallium neutrino anomaly through a new detection channel. Such a measurement could allow us to pinpoint the origin of this long-standing puzzle, discriminating between a miscalculation of the source activity and any possible gallium-related effects.
In this contribution, we will present the requirements for a future lithium-based bolometric experiment and its sensitivity for a cross-check of the Gallium neutrino anomaly via the CEvNS detection.
