ARTIC (Argon Test Infrastructure), is a cryogenic facility installed in the DIFILab laboratory of the Physics Department of the University of Genoa, consisting of a large cryostat (1 m in diameter and 1.5 m in height) designed for the development and testing of liquid argon detectors.
Liquid Argon detectors, conceived in the 1980s by Carlo Rubbia, are by now very widespread in neutrino physics experiments and for the direct search for dark matter. Given the properties of liquid Argon which produces both ionization charge and scintillation light when charged particles pass through it, it is in fact possible to construct detectors capable of exploiting both charge and light signals for the spatio-temporal reconstruction of the trace of the particle with very high precision even on large volumes. Since neutrino physics experiments and direct dark matter searches need large masses to increase the number of neutrino interactions or possible dark matter, detectors based on liquid argon technology are particularly suitable, thanks to the fact that they can easily be scaled up to masses of several tons, while still ensuring accurate particle tracking information and identification of the type of particle that produced it.
In ARTIC, innovative detectors based on a light focusing optical system capable of operating at cryogenic temperatures and with ultraviolet scintillation light will be tested for the first time. The detectors have been designed to visualize tracks of charged particles passing at a distance between 40 and 100 cm from the detector and in ARTIC they will be characterized both with a mobile artificial light source inside the cryostat and through the observation of muons cosmic waves acquired in coincidence with a simple detector located outside the cryostat. If the results are satisfactory, the innovative detectors will be installed inside the SAND detector in the Near Detector Complex of DUNE, a new generation experiment, currently in the designing phase, which has the aim of accurately measuring the oscillation parameters of neutrinos and to discover asymmetry between matter and antimatter.
Furthermore, ARTIC is a facility of the Department that can host other types of detectors or prototypes and can be very useful for mechanical or functional tests at cryogenic temperature. In recent years, some prototypes of the DarkSide experiment for the direct search for dark matter have been tested in ARTIC.
In the coming years, the facility will be integrated with a liquid Argon recirculation and purification system in order to allow the use of the cryostat also for precision measurements of the light sensor efficiency and for the characterization of the scintillation light.