One event - and now? An overview of LZ’s recent high-energy results

by Theresa Fruth (University of Sydney)

Thursday 8 Oct 2026, 16:00 → 17:00 Australia/Sydney

LUX-ZEPLIN (LZ) is a dark matter direct detection experiment located at the Sanford Underground Research Facility in Lead, South Dakota. At the heart of the detector is a dual-phase time projection chamber containing 7 tonnes of active liquid xenon. With a combined exposure of 4.2 tonne-years from the first two science campaigns, LZ has placed the most stringent limits on the spin-independent WIMP-nucleon cross section, down to 2.2 x 10^-48 cm^2 for a 40 GeV/c^2 WIMP mass. More surprisingly, in a search for effective field theory and inelastic dark matter models with an extended energy window up to 270 keV, LZ has now observed one event with a characteristic energy consistent with a nuclear recoil of 248 ±23 (stat) ±23 (sys) keV, in a region where the known background expectation is low. A profile likelihood ratio test finds tension with the background-only hypothesis at a global significance of 2.6σ when accounting for look-elsewhere effects, with a maximum local significance of 3.4σ across the models tested. In this talk, I will discuss the analysis, the backgrounds considered and what comes next.