Argon Depletion for a Large Scale Dark Matter Detector

Argon depleted of $^{39}$Ar utilizing thermal diffusion methods is being implemented in 20 columns at USD.~ Thermal diffusion~is a well-known technique in isotope separation. The columns are 3 meters long and 0.5 inch in diameter.~ This test system will allow us to deplete $^{39}$Ar by a factor of 10 for 1 kg of natural argon over two months. This would lead to the full-scale production of depleted argon by using more columns that are longer in length. This depleted argon can then be used as a target material for next generation dark matter detectors. Using an advanced automation~system,~we can run our test system continuously to extract the enriched $^{39}$Ar for eventual measuring at ANL. The interim results of the test system will be reported utilizing the more abundant isotope $^{36}$Ar. In addition, the current effort for obtaining $^{39}$Ar results will be presented.