Radon daughter removal from PTFE surfaces and its application in liquid xenon detectors

Abstract

Long-lived radon daughters are a critical background source in experiments searching for low-energy rare events. Originating from radon in ambient air, radioactive polonium, bismuth and lead isotopes plate-out on materials that are later employed in the experiment. In this paper, we examine cleaning procedures for their capability to remove radon daughters from PTFE surfaces, a material often used in liquid xenon TPCs. We found a large difference between the removal efficiency obtained for the decay chains of ${}^{222}$Rn and ${}^{220}$Rn, respectively. This indicates that the plate-out mechanism has an effect on the cleaning success. While the long-lived ${}^{222}$Rn daughters could be reduced by a factor of ~2, the removal of ${}^{220}$Rn daughters was up to 10 times more efficient depending on the treatment. Furthermore, the impact of a nitric acid based PTFE cleaning on the liquid xenon purity is investigated in a small-scale liquid xenon TPC.

References in corpus (2)

• Transmission of xenon scintillation light through PTFE
• Radon Daughter Plate-out onto Teflon

Cited by in corpus (11)

• The XENONnT Dark Matter Experiment
• Characterization of alpha and beta interactions in liquid xenon
• Design and construction of Xenoscope -- a full-scale vertical demonstrator for the DARWIN observatory
• Reduction of ${}^{222}$Rn-induced Backgrounds in a Hermetic Dual-Phase Xenon Time Projection Chamber
• Production and characterization of a ${}^{222}$Rn-emanating stainless steel source
• Scintillation decay-time constants for alpha particles and electrons in liquid xenon
• AlphaCAMM, a Micromegas-based camera for high-sensitivity screening of alpha surface contamination
• Particle background characterization and prediction for the NUCLEUS reactor CE$\nu$NS experiment
• Exploration of Methods to Remove Implanted ${}^{210}$Pb and ${}^{210}$Po Contamination from Silicon Surfaces
• Material radiopurity control in the XENONnT experiment
• Removal of radon progeny from delicate surfaces