Status of the XENONnT dark matter experiment.

Di Gangi P.
  Giovedì 15/09   15:00 - 18:30   Aula T - Caterina Scarpellini   III - Astrofisica   Presentazione
XENONnT is a dark matter direct detection experiment located at the INFN, Laboratori Nazionali del Gran Sasso. The core detector is a dual-phase time projection chamber (TPC) filled with $5.9 {t}$ of liquid xenon and instrumented with a total of 494 photomultiplier tubes (PMTs). The TPC is installed in the center of a stainless-steel tank filled with $700 {t}$ of water instrumented with 84 PMTs and operated as an active water Cherenkov Muon Veto (MV). A novel sub-detector, the Neutron Veto (NV), is contained within the MV and surrounds the TPC in order to suppress the neutron background. The highly reflective NV volume is optically separated from the Muon Veto and instrumented with 120 high-$QE$ low-radioactivity PMTs. The water will be eventually doped with gadolinium to maximize the neutron detection efficiency. In 2020 XENONnT replaced the successful XENON1T experiment, which was the world's most sensitive detector for direct dark matter searches. After a few months of commissioning, since mid-2021 XENONnT started its science data acquisition. In this contribution we will review the most relevant achievements of XENON1T, and describe the concept, the performances and the scientific program.