ausblenden:
Schlagwörter:
-
Zusammenfassung:
An important background in detectors using liquid xenon for rare event searches arises from the decays of radon and its daughters. We report for the first time a reduction of Rn-222 in the gas phase above a liquid xenon reservoir. We show a reduction factor of >= 4 for the Rn-222 concentration in boil-off xenon gas compared to the radon enriched liquid phase. A semiconductor-based alpha-detector and miniaturized proportional counters are used to detect the radon. As the radon depletion in the boil-off gas is understood as a single-stage distillation process, this result establishes the suitability of cryogenic distillation to separate radon from xenon down to the 10(-15) mol/mol level.