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Title: Liquid-phase purification for multi-tonne xenon detectors

As liquid xenon detectors grow in scale, novel techniques are required to maintain sufficient purity for charges to survive across longer drift paths. The Xeclipse facility at Columbia University was built to test the removal of electronegative impurities through cryogenic filtration powered by a liquid xenon pump, enabling a far higher mass flow rate than gas-phase purification through heated getters. In this paper, we present results from Xeclipse, including measured oxygen removal rates for two sorbent materials, which were used to guide the design and commissioning of the XENONnT liquid purification system. Thanks to this innovation, XENONnT has achieved an electron lifetime greater than$${10}\,\hbox {ms}$$10msin an$$\sim {8.6}{\text {tonne}}$$8.6tonnetotal mass, perhaps the highest purity ever measured liquid xenon detector.

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Award ID(s):
1719286 2112851
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Springer Science + Business Media
Date Published:
Journal Name:
The European Physical Journal C
Medium: X
Sponsoring Org:
National Science Foundation
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