Speaker
Description
The NEWS-G3 experiment aims at the detection of reactor neutrinos using a 60cm-diameter Spherical Proportional Counter (SPC) at high pressure. The low energy threshold down to single-electron detection and the electron-counting capabilities, allow for the detection of low energy nuclear recoils, with an estimated event rate of 5 events/bar/day/GW in argon at 20m from the reactor core. Flexibility in the choice of gas target allows for probing the CEvNS cross-section for different isotopes while the detector operates on site.
The G3 detector consists of a low-radioactivity copper sphere, enclosed in a cube compact shield made of layers of copper, polyethylene and lead. In addition, the shield is composed of a layer of twelve plastic scintillators acting as an active muon-veto. Calibrations up to 10 bar of pressure in Ar+2%CH4 have been conducted using a 30cm-diameter test detector. In order to limit voltage demands and prevent discharges, sensors with sub-mm anodes have been constructed down to 0.25mm in diameter. In addition, background simulations have been performed using GEANT4, expecting approximately 97% veto efficiency for the muon-induced background at sub-keV energies.
