Dark matter. The LUX-ZEPLIN (LZ) project is a dark matter experiment selected by the Department of Energy (DOE) as the flagship U.S. dark matter experiment. It is located deep underground, at the 4850' level of the Sanford Underground Research Facility (SURF) in Lead, South Dakota. The heart of the detector is a dual-phase time projection chamber (TPC), containing 7 tonnes of liquid xenon in the central active volume. The experiment has been designed to reach unprecedented sensitivity in the search for dark matter particles in the form of weakly interacting massive particles (WIMPs). These particles are detected by looking for the rare interactions produced by nuclear recoils in the active liquid xenon target. This active volume is viewed by two arrays of light detectors to detect signal interactions while being surrounded by veto detectors to improve background rejection in the central TPC.

See this article https://arxiv.org/pdf/1910.09124.pdf for more details on LZ.

Ultra-high-energy cosmic rays and neutrinos. The origin of ultrahigh-energy cosmic rays presents a tanalizing puzzle. Experiments have observed cosmic ray particles, each of which carries as much energy as a bullet shot from a rifle. The problem is twofold: it is difficult to accelerate particles to such enormous energies, and it is also hard to understand how these particles could reach us from large distances, despite their interactions with the cosmic microwave background radiation. Theorists have explored various possible explanations, some of which point to new phyisics. Theorists in our group work closely with the experimentalists; in particular, Graciela Gelmini and Alex Kusenko are members of the Pierre Auger collaboration.

Baryogenesis. Although every particle has its antiparticle, there is no antimatter in the observed universe. The process in which the matter-antimatter asymmetry was produced in the early universe, called baryogenesis, remains a mystery. A number of solutions have been proposed. One possibility, the so called Affleck-Dine baryogenesis, could have taken place in the early universe if supersymmetry is right and if cosmological inflation took place. This process could produce both ordinary matter and dark matter.