Speaker
Aiwu Zhang
(Brookhaven National Laboratory)
Description
For neutrino oscillation experiments such as DUNE that utilize very large volume of liquid argon (LAr) as the detection medium, it is critical to remove and control impurities (such as oxygen, water, etc.) to extremely low levels (<1 ppb) in order to achieve unprecedented energy scale precision. It is thus desired to have a verified mathematical model describing the dynamics of impurity distributions in any LAr detectors. The model presented in this talk considers the full dynamic components influencing the purity performance of a LAr detector, including sources, sinks, and transport of impurities within and between the gas and liquid argon phases.
An analytical solution is provided after simplifying the model by ignoring a few components which have least significant influences. This solution predicts a way to measure the ratio of impurity concentrations between gas and liquid argon phases, also known as the Henry’s coefficient. This method is applied on a 20-L LAr multipurpose test stand with gas argon purification and condensation functionalities. The Henry's coefficient for oxygen is extracted to be 0.83 $\pm$ 0.04, which is in good agreement with past measurements. A first measurement of the Henry's coefficient for water is carried out and preliminary result will be presented. Some other aspects about this model will be discussed.
Primary authors
Aiwu Zhang
(Brookhaven National Laboratory)
Craig Thorn
(Brookhaven National Lab)
Dr
Yichen Li
(Brookhaven National Lab)
Co-authors
Chao Zhang
(Brookhaven National Lab)
James Stewart
(Brookhaven National Lab)
Milind Diwan
(Brookhaven National Lab)
Steve Kettel
(Brookhaven National Lab)
Xin Qian
(Brookhaven National Lab)
