Ponente
Descripción
DarkSide-20k is a next-generation, direct dark matter search experiment
located at LNGS (Italy), aiming for a background-free exposure of 200 tonne-years,
i.e < 0.1 neutron WIMP-like event. The core of the detector is a dual-phase
Time Projection Chamber (TPC) filled with 50 tonnes of low radioactivity
liquid argon. The entire TPC wall is surrounded by a 15 cm of pure
polymethylmethacrylate (PMMA), which acts as a neutron veto, immersed in
a second low-radioactivity liquid argon bath enclosed in a stainless steel
vessel. The entire detector is enclosed in a protoDUNE-like cryostat filled with
600 tons of atmospheric argon. TPC and neutron veto are equipped with
large-area Silicon Photomultiplier (SiPM) array detectors. SiPMs are arranged
in a compact design intended to minimise the material used for circuit boards,
cables, and connectors, forming a photo-detection unit.
A central challenge for achieving the experiment’s sensitivity goal, 7.4 x 10-48
cm2 for 1 TeV WIMP, is ensuring a stringent radiopurity. In this talk, I will
present the comprehensive radiopurity strategy adopted by DarkSide-20k,
including the material assay campaign, selection procedures, and
Implementation of a radiopurity protocol throughout the detector construction
phase. I will also provide an overview of background sources and detail the
mitigation techniques employed to reach the experiment’s ambitious
background-free target.
