Letter of Intent: Large-scale demonstration of the ARIADNE LArTPC optical readout system at the CERN Neutrino Platform

Optical readout of dual phase liquid argon TPCs has been successfully demonstrated by the ARIADNE 1-ton experiment to be a very viable and attractive alternative to charge readout. TPX3 cameras have been shown to be capable of providing a full 3D event reconstruction. In this letter of intent we describe optimisation and testing of the TPX3 camera based technology at a large scale for the potential use in a DUNE kton-scale module. To this end we propose instrumenting the existing 5mx5m CERN cryogenic vessel at the Neutrino Platform with TPX3 cameras. Four TPX3 cameras with a total field of view of 2mx2m will collect the secondary scintillation light produced in the THGEM holes. Cosmic ray data will be collected and a stopping muon analysis will be performed.