Building a New Cryoprobe System for Barium Tagging in Liquid Xenon

nEXO is a planned search for neutrinoless double beta decay in liquid xenon, and barium tagging (the identification of the daughter barium) has emerged as a desired technique for background discrimination. A scheme for barium tagging involving cryoprobe extraction and spectroscopic identification is being developed at CSU. The next generation of a liquid xenon system is being developed with a new recirculating helium-based cryoprobe to operate at lower temperatures than previous probes. This new iteration of the system contains several new and reworked components designed to improve performance. Among these are the addition of a thermal insulator to focus the cooling on the deposition window as well as a redesign of the electrodes used to guide the barium to the window.