Speaker
Description
The NUCLEUS experiment aims to detect Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) using reactor antineutrinos from the Chooz nuclear power plant, with ultra-low-threshold CaWO4 cryogenic targets. To achieve the ambitious particle background goal of the order of 100 dru in the CEvNS region of interest (20-200 eV), a multi‑stage rejection strategy is employed, combining passive shielding and active veto systems both at warm and cryogenic temperatures.
A key component of this strategy is the Cryogenic Outer Veto (COV), which consists of six charge readout high purity germanium detectors, two cylindrical and four rectangular, directly surrounding the cryogenic targets, providing 4pi coverage and operated at 10 mK. The COV's background suppression capabilities are directly tied to the energy threshold of these detectors, motivating dedicated noise reduction and analysis efforts.
In this poster, I will present latest results from the first commissioning tests at the Chooz site, as well as new analysis and filtering techniques that exploit noise correlations between detectors to further reduce detector noise and improve the COV threshold, ultimately supporting the experiment's sensitivity goal.