Direct search for WIMP dark matter particles with the LUX-ZEPLIN (LZ) detector

LZ is a second-generation Dark Matter experiment to conduct searches for weakly interacting massive particles. It is expected that the detector will reach a sensitivity for spin-independent elastic WIMP-nucleon cross-section of 1.6×10−48cm2 at a mass of 40 GeV/c2 in 1000 days of operation. Aside from Dark Matter particle interactions, the detector will also be sensitive to solar and supernova neutrinos as well as neutrinoless double beta decay from 136Xe. Background sources such as 222Rn and 85Kr must be significantly suppressed. This will be assured by radioactive screening of detector components and purification of xenon. The design of the LZ detector, radioactive background expectations and projected WIMP sensitivity are presented in this article.