Probing the Scalar WIMP-Pion Coupling with the first LUX-ZEPLIN data

Abstract

Weakly interacting massive particles (WIMPs) may interact with a virtual pion that is exchanged between nucleons. This interaction channel is important to consider in models where the spin-independent isoscalar channel is suppressed. Using data from the first science run of the LUX-ZEPLIN dark matter experiment, containing 60 live days of data in a 5.5~tonne fiducial mass of liquid xenon, we report the results on a search for WIMP-pion interactions. We observe no significant excess and set an upper limit of $1.5\times 10^{-46}$~cm${}^2$ at a 90\% confidence level for a WIMP mass of 33~GeV/c${}^2$ for this interaction.