Speakers
Description
A new ultra-cold neutron (UCN) detector is required for the n2EDM experiment since the previous $^6$Li-doped glass scintillator (NANOSC) model, used in the nEDM experiment, is constrained by its small size and high price (\textcolor{red}. Hence, the authors propose a novel detector (GADGET) composed of a chamber filled with $^3$He and CF$_4$ gases, and three perpendicular photo-multiplier tubes coupled to it. In order to access the optimal gas pressures, two experiments, one at the Paul Scherrer Institute with a pulsed UCN beam, and the other at the Mainz's TRIGA reactor with constant UCN flux, were carried out. As a result, under conditions of 400 mbar for CF$_4$ and 25 mbar for $^3$He, a relatively higher detection efficiency (twice the one of a Cascade detector) and a great background suppression (estimated in a 2\% of the total counts at PSI) were achieved. In addition, to further improve the light emission properties of GADGET, tests with new customized photo-multiplier tubes, thinner entrance foils and higher transmittance chamber windows are also discussed.
