Lucie Tvrznikova (Yale) "Sub-GeV dark matter searches and electric field studies for the LUX and LZ experiments "

ABSTRACT:
The Large Underground Xenon (LUX) and the LUX-ZEPLIN (LZ) detectors were designed to directly observe the interaction of dark matter (DM) with xenon target nuclei and thus probe much of the unexplored DM parameter space. I will discuss two novel direct detection methods, Bremsstrahlung and the Migdal effect, that were used by LUX to place limits on DM with masses of 0.4-5 GeV. I will also describe the development of a fully 3D model of electric fields that varied during the detector’s final 332 live-days of data acquisition. Since direct measurement of electric fields was not possible, this work enabled a thorough understanding of the detector throughout its operation. Lastly, I will present new results from the Xenon Breakdown Apparatus (XeBrA) built at LBNL to characterize the dielectric breakdown under high voltage in liquid xenon and liquid argon. Results from XeBrA will inform LZ and the future of noble liquid detector engineering.