Xenon-Argon Technology

The Motivations

Xe-Ar technology has generated a great interest in the particle physics community over the last decade. With only a few ppm of Xe, in fact, such a mixture eliminates the need for a wavelength shifter, which absorbs and isotropically re-emits light, quenches the LAr slow scintillation component, and finally increases the attenuation length of the light. These properties make the Xe-Ar mixture very attractive for particle detectors in the search for interactions with energies ranging from tens of eV to several GeV.

Although the application field of Xe-Ar technology is very broad, even beyond particle detection, the thermodynamics of the Xe-Ar mixture is not yet fully assessed. Xe-Ar detectors operate at atmospheric pressure and at temperatures for which the mixture Xe-Ar is in the liquid phase. The detector temperature is the one normal boiling Ar (87.3 K) and much lower than the Xe triple point temperature (161.4 K). As a consequence, the maximum Xe content in the Xe-Ar mixture is imposed by the solubility limit of solid Xe in LAr. To determine this limit and the temperature-pressure region of existence of the Xe-Ar liquid phase, the precise knowledge of the Xe-Ar phase diagram is required. Although noble gasses have been widely studied, only few literature data exist for the Xe-Ar mixture.

The Scope

The goal of this project is to characterize both particle detection (scintillation and ionization) and thermodynamic properties of the Xe-Ar mixture. The proposed project encompasses a combination of state-of-the-art experiments, theoretical developments, and innovative and challenging simulations with exciting prospects in fields ranging from fundamental physical-chemistry to astrophysics and medical sciences.