HEP-Astro Seminar | LZ: First Dark Matter Search Results and How We Got There

Strong evidence exists for the presence of dark matter in the universe however its nature remains a mystery. For many years a multitude of experiments have looked for the dark matter particle without success, but carving out large chunks of excluded parameter spaces.

LUX-ZEPLIN (LZ) is a dark matter direct detection experiment consisting of a dual-phase xenon Time Projection Chamber and surrounded by an active Xe skin veto and an active gadolinium-loaded liquid scintillator outer detector. It is placed within an ultrapure water shield and located a mile underground at the Sanford Underground Research Facility in Lead, South Dakota.

The LZ collaboration has now published the results for its first search for Weakly Interacting Massive Particles (WIMPs). This result utilized a fiducial mass of 5.5 tonnes of Xe and an exposure of 60 live days. LZ achieved world-leading sensitivity, setting new limits on spin-independent WIMP-nucleon cross-sections for WIMP masses above 9 GeV. In addition, this first run demonstrated the capabilities of the LZ experiment and informed us as to what we can expect in the years to come.

In this talk I will given an overview of the LZ detector, with a bit more focus than usual on its construction and operations, and a description of the analysis that brought us these first results.