First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment
The nature and origin of dark matter are among the most compelling mysteries of contemporary science. There is strong evidence for dark matter from its role in shaping the galaxies and galaxy clusters that we observe in the universe. For over three decades, physicists have been trying to detect the dark matter particles themselves with ever more sensitive instruments.
LUX-ZEPLIN (LZ) is a dark matter direct detection experiment located at the Sanford Underground Research Facility in Lead, South Dakota. The LZ detector consists of a dual-phase xenon Time Projection Chamber with an active volume of 7 tonnes, shielded by an active liquid xenon skin region, an active gadolinium-loaded liquid scintillator veto, and an ultrapure water veto.
The LZ collaboration recently published the results for its first search for Weakly Interacting Massive Particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 tonnes. The detector achieved world-record sensitivity to a vast range of dark matter particles, setting new limits on spin-independent and spin-dependent WIMP-nucleon cross-sections for WIMP masses above 9 GeV.
This talk will give an overview of the LZ detector, a description of the first results, and a brief look at the broad dark matter and neutrino science program that is now accessible with the experiment.
Maria Elena Monzani is a Lead Scientist at SLAC. Her research field is astroparticle physics, which focuses on topics at the intersection between particle physics and astrophysics/cosmology. She received a joint PhD from the University of Milano and the University of Paris 7. She held a postdoctoral position at Columbia University, before joining SLAC in 2007 to work on the Fermi Gamma-ray Space Telescope. Today, Monzani is the deputy operations manager for the LZ Dark Matter Experiment, where she leads the Software and Computing effort.
Tomasz Biesiadzinski received his PhD from the University of Michigan, subsequently joining the LZ group at Case Western Research University for his postdoctoral training. He joined SLAC as a Research Associate in 2014, and he is now a Project Scientist. Biesiadzinski is the "Level-2” manager for Detector Operations for the LZ Dark Matter Experiment, and has led the installation, integration, and commissioning of the whole experiment. He is a frequent visitor at SURF lab in South Dakota, and is in charge of ensuring that LZ runs smoothly.
Alden Fan has been working on Noble Liquid Dark Matter Detectors for the entirety of his career. He received his PhD from UCLA working on the DarkSide experiment, and joined SLAC as a Kavli Fellow in 2016. He currently works as a Project Scientist in the Fundamental Physics Directorate. Fan is the deputy Physics coordinator for the LZ collaboration, and he leads the analysis effort to search for WIMP interactions in LZ data. He served as the corresponding author for the paper describing the first dark matter search results from the experiment.