SMuK 2023 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
T: Fachverband Teilchenphysik
T 14: Neutrinos, Dark Matter II
T 14.2: Talk
Monday, March 20, 2023, 16:45–17:00, HSZ/0002
Radon removal in the XENONnT experiment via cryogenic distillation — •Henning Schulze Eißing1, Lutz Althüser1, Christian Huhmann1, David Koke1, Andria Michael1, Michael Murra2,1, Philipp Schulte1, and Christian Weinheimer1 for the XENON collaboration — 1Institut für Kernphysik, Universität Münster — 2Columbia University, New York, USA
In order to reduce the dominant component of the electronic recoil background, Rn-222 and its progenies, in the XENONnT experiment a high flux radon removal system has been build by our group (Eur. Phys. J. C 82 (2022) 1104). Rn-222 continuously emanates from detector components and distributes homogeneously within the liquid xenon target due to the half-life of 3.8 days.
Our active radon removal system utilizes the vapor pressure difference between radon and xenon in the form of a cryogenic distillation column. With a xenon flow of 200 slpm the full 8.6 t of xenon are passed through the column within one mean lifetime of Rn-222 resulting in a radon concentration reduction by a factor two. An additional extraction flow of 25 slpm from the xenon gas phase provides a further reduction factor of about two. Combining both methods we achieved a radon activity concentration as low as 1 muBq/kg, the lowest value to date with a xenon-based Dark Matter experiment.
This talk will outline the working principle of the radon removal system and the performance within the XENONnT experiment.
This work is supported by BMBF under contract 05A20PM1 and by DFG within the Research Training Group GRK 2149.