Speaker
Description
Xenon and argon are widely used target media for low cross-section experiments including neutrino physics and dark matter searches. Xenon-doping of dual phase argon time projection chambers (TPCs) at the O(1%) level may enable these technologies to reach unprecedented sensitivity limits. However, the large temperature discrepancy between the argon and xenon boiling points can produce instabilities in a xenon-doped argon detector such as unwanted xenon distillation. Due to the challenging nature of maintaining mixture stability in xenon-doped liquid argon, it is desirable to develop sensors which can precisely measure changes in xenon concentration. We have built a custom capacitor that utilizes the difference in xenon and argon atomic polarizability to measure the xenon concentration in liquid argon with a precision of 0.1%. This talk will discuss the application of this capacitor to monitor the xenon concentration in a dual phase argon detector doped with xenon at 2.35% by molar fraction.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory (LLNL) under Contract DE-AC52-07NA27344 and was supported by the LLNL-LDRD Program under Project No. 20-SI-003. It is also supported by the U.S. Department of Energy (DOE) Office of Science, Office of High Energy Physics under Work Proposal Number SCW1676 awarded to LLNL. J. Kingston is supported by the DOE/NNSA under Award Number DE-NA0000979 and DE-NA0003996 through the Nuclear Science and Security Consortium.
