Â鶹ÍøÕ¾

Michela Lai
University of California Riverside

Abstract

Since the 1930s, many astrophysical and cosmological observations have motivated the search for dark matter particles, building a wide variety of experiments specifically designed to perform their very first direct detection. Liquid argon is one of the most sensitive targets for GeV-scale candidates, such as Weakly Interacting Massive Particles (WIMPs), as demonstrated so far by the DEAP-3600 experiment and DarkSide-50 experiment, featuring respectively a 3.3 tonne single-phase and a 50 kg double-phase Time Projection Chamber design. In the meantime, unique R&D has led to the design of the first experiment within the Global Argon Dark Matter collaboration, DarkSide-20k, currently under construction at LNGS. Its 50-tonne ultra-pure argon target, together with the extraordinarily low background level, will allow for investigating for the very first time in argon dark matter-nucleon cross-section as low as 7.4 x 10^{-48} cm^2 for a WIMP mass of 1 TeV/c^2 in a 200 t yr run.

DarkSide-20k, and after it, ARGO, will give the ultimate answer to whether WIMPs exist and whether we can detect them. But there is more to investigate with noble liquids. Argon detectors are indeed not only the favorite for ultra-heavy dark mark candidates but are also at the very center of a multi-messenger physics program, including the detection of neutrinos released by core-collapse supernovae, by neutron star binary mergers as well as by the accretion disk on black holes. While extending the physics program of argon detectors, we will also investigate how we can push their sensitivity to sub-GeV dark matter candidates by just adding a few part-per-millions of xenon or other photosensitive dopants. If scaled to a tonne-scale experiment, this innovative technology will pave the way for searching unexplored dark matter candidates while opening a new window into our Universe.

Timbits, coffee, tea will be served in STI AUD before the colloquium.