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arXiv · 2209.00362

Reduction of $^{222}$Rn-induced Backgrounds in a Hermetic Dual-Phase Xenon Time Projection Chamber

Julia Dierle·Adam Brown·Horst Fischer·Robin Glade-Beucke·Jaron Grigat·Fabian Kuger·Sebastian Lindemann·Mariana Rajado Silva·Marc Schumann
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Abstract

The continuous emanation of $^{222}$Rn from detector surfaces causes the dominant background in current liquid xenon time projection chambers (TPCs) searching for dark matter. A significant reduction is required for the next generation of detectors which are aiming to reach the neutrino floor, such as DARWIN. $^{222}$Rn-induced back\-grounds can be reduced using a hermetic TPC, in which the sensitive target volume is mechanically separated from the rest of the detector containing the majority of Rn-emanating surfaces. We present a hermetic TPC that mainly follows the well-established design of leading xenon TPCs and has been operated successfully over a period of several weeks. By scaling up the results achieved to the DARWIN-scale, we show that the hermetic TPC concept can reduce the $^{222}$Rn concentration to the required level, even with imperfect separation of the volumes.

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Julia Dierle, Adam Brown, Horst Fischer, Robin Glade-Beucke, Jaron Grigat, Fabian Kuger, Sebastian Lindemann, Mariana Rajado Silva, Marc Schumann. 2022-09-01. Reduction of $^{222}$Rn-induced Backgrounds in a Hermetic Dual-Phase Xenon Time Projection Chamber. https://doi.org/10.1140/epjc%2Fs10052-022-11151-w

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