The Yossef Dothan Memorial Lecture: "Direct Detection of sub-GeV Dark Matter: A New Frontier "
Professor Rouven Essig
C.N. Yang Institute for Theoretical Physics
Stony Brook University, New York, USA
Professor Rouven Essig is a Guest Lecturer at the Emilio Segre Distinguished Lectures in Physics endowed by Raymond and Beverly Sackler for the academic year 2022/2023, delivering the annual Yossef Dothan Memorial Lecture.
Dark matter makes up 85% of the matter in our Universe, but we have yet to learn its identity. While most experimental searches focus on Weakly Interacting Massive Particles (WIMPs) with masses above the proton (about 1 GeV/c^2), many natural dark-matter candidates have masses below the proton and are invisible in traditional WIMP searches. In this talk, I will discuss the search for dark matter with masses between about 500 keV/c^2 to 1 GeV/c^2 (“sub-GeV dark matter”), which has seen tremendous progress in the last few years. I will describe several direct-detection strategies, and discuss how to search for dark matter interactions with electrons and nuclei in various target materials, such as noble liquids and semiconductors. I will in particular highlight SENSEI, a funded experiment that uses ultra-low-threshold silicon CCD detectors (“Skipper CCDs”) capable of detecting even single electrons. I will describe the latest results from SENSEI, and how SENSEI and other experiments expect to probe orders of magnitude of novel dark matter parameter space in the next few years.