Depleted Argon from Underground Sources

10 Jun 2011, 16:00
20m
Chicago Ballroom 10 (Sheraton Hotel)

Chicago Ballroom 10

Sheraton Hotel

Oral Presentation Dark Matter Detectors Dark Matter Detectors

Speaker

Dr Henning Back (Princeton University)

Description

Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic 39Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in 39Ar. In Cortez Colorado a CO2 well has been discovered to contain approximately 500ppm of argon as a contamination in the CO2. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N2, and He mixture, from the CO2 through chromatographic gas separation. The N2 and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

Author

Dr Henning Back (Princeton University)

Co-authors

Prof. Andrew Alton (Augustana College) Mr Augusto Goretti (Princeton University) Mr Ben Loer (Princeton University) Mr Cary Kendziora (Fermi National Accelerator Laboratory) Prof. Cristiano Galbiati (Princeton University) Mr David Montanari (Fermi National Accelerator Laboratory) Prof. Frank Calaprice (Princeton University) Mr Pablo Mosteiro (Princeton University) Dr Stephen Pordes (Fermi National Accelerator Laboratory)

Presentation materials