The NUCLEUS experiment aims at a high-precision measurement of the coherent elastic neutrino-nucleus scattering (CEνNS). This process is a unique tool to search for new physics beyond the Standard Model and to understand the properties of its most elusive particles, neutrinos.

NUCLEUS is developing cryogenic detectors with an unprecedentedly low energy threshold to be operated at the Chooz nuclear power plant in France. This nuclear reactor will deliver a large flux of anti-neutrinos with typical energies of a few MeV, enabling the study of CEνNS with high statistics.

NUCLEUS comprises two phases:

  1. in the first scientific run (starting in 2021) we will deploy a detector with an active mass of 10 grams. We will measure for the first time CEνNS at nuclear reactors, aiming at a precision better than 10% on its cross-section within 1 year of live-time. NUCLEUS-10g will prove that the proposed technology allows to reach an energy threshold as low as 10 eV, offering the new possibility to investigate for the first time the antineutrino spectrum below 1.8 MeV.
  2. In a later phase (starting in 2023) we will increase the detector mass up to 1 kg exploiting new technological approaches, such as frequency multiplexed transition edge sensors and Kinetic Inductance Detectors. Our main goal will be the achievement of a precision at the level of 1% on the CEνNS cross-section.

The high precision reached by NUCLEUS will open the door for the study of physics beyond the Standard Model of Particle Physics such as the search for non-standard neutrino interactions, a neutrino magnetic dipole moment or exotic neutral currents, as well as a test of the Reactor Antineutrino Anomaly.

The members of the NUCLEUS collaboration come mostly from Germany (PI: Raimund Strauss), Italy, France and Austria. In Italy, NUCLEUS is supported by INFN.