Speaker
Description
LUX-ZEPLIN (LZ) is a dual phase xenon time projection chamber, searching for WIMP dark matter, and other rare phenomena. Decays from the $^{222}$Rn chain pose a dominant background in LZ, requiring multiple mitigation strategies targeting either $^{222}$Rn or its daughters. One method utilised by LZ is an inline radon removal system, separating radon from gaseous xenon using a charcoal chromatography column. Continued progress in the search for dark matter will require more sensitive experiments with more stringent radiogenic background controls. An alternative approach to radon removal is therefore necessary for the next-generation of experiments. This talk presents the first measurements of the effectiveness of radon removal with a charcoal chromatography column in the liquid phase, performed at SLAC, USA. We find an adsorption coefficient in liquid 3 orders of magnitude lower than in the gas phase, rendering charcoal chromatography an ineffective method for liquid-phase radon removal.