Speaker
Description
Coherent elastic neutrino-nucleus scattering (CEvNS) is a weak neutral-current process predicted by the Standard Model of Particle Physics. A neutrino scatters elastically and coherently off a nucleus, yielding a low-energy nuclear recoil in the eV-keV range. Such a low-energy signature makes the detection of the process extremely challenging.
The NUCLEUS experiment, located at the Chooz nuclear power plant, aims to study CEvNS on tungsten nuclei using neutrinos produced by the two 4.25 GWth reactor cores. To do so, NUCLEUS deploys gram-scale CaWO4 crystals, operated as cryogenic calorimeters with an ultra-low nuclear recoil energy threshold of O(10) eV. The crystals are instrumented with Transition Edge Sensors, operated at ~10 mK, to read out the phonon signal directly. The shallow overburden provided by the site also requires an elaborate system of active vetoes and passive shielding to mitigate the backgrounds.
After a commissioning phase, the experiment is starting to collect data in a year-long technical run, to assess noise and background conditions in-situ, as well as to set first limits on the CEvNS cross section on tungsten and constrain beyond-the-Standard-Model interactions. In the talk, I will present an update on the latest developments of NUCLEUS.