Searching for Dark Matter with Direct Detection Experiments

Dark matter constitutes about 85% of the matter content of the Universe, yet its nature remains one of the most important open questions in fundamental physics. Among the many proposed candidates, Weakly Interacting Massive Particles (WIMPs), axions and axion-like particles, and other light dark matter scenarios are particularly well motivated. In recent years, the experimental landscape has expanded significantly, with dedicated searches exploring dark matter candidates over an extremely wide mass range through complementary techniques.

In this seminar, I will review the principles and current status of direct dark matter detection experiments. I will briefly discuss axion and ultralight dark matter searches before focusing on direct searches for WIMPs and light dark matter candidates. These experiments aim to observe the tiny energy deposits produced by dark matter interactions in ultra-low background detectors located underground. I will discuss the main detection strategies and the exploration of both the traditional WIMP parameter space and lighter dark matter scenarios. Then I will focus on my research activities in the ANAIS-112 and DarkSide-20k experiments. ANAIS-112, operating at the Canfranc Underground Laboratory, searches for the annual modulation signature reported by DAMA/LIBRA using NaI(Tl) scintillators and provides a model-independent test of this long-standing claim. I will present the current status and most relevant results of the experiment. I will also discuss the DarkSide-20k experiment, a next-generation liquid argon detector designed to achieve unprecedented sensitivity to WIMP dark matter through ultra-low background techniques, powerful background
discrimination capabilities, and large target mass.