New method of 85Kr reduction in a noble gas based low-background detector. (6th April 2017)

• Record Type: Journal Article
• Authors: Akimov, D.Yu.; Bolozdynya, A.I.; Burenkov, A.A.; Hall, C.; Kovalenko, A.G.; Kuzminov, V.V.; Simakov, G.E.
• Is Part Of: Journal of instrumentation. Volume 12:Number 4(2017:Apr.)
• Page Start: P04002
• Page End: P04002
• Publication Date: 2017-04-06
• Subjects: Dark Matter detectors (WIMPs, axions, etc.) -- Noble liquid detectors (scintillation, ionization, double-phase); Scientific apparatus and instruments -- Periodicals; 502.84
• DOI: 10.1088/1748-0221/12/04/P04002
• Languages: English
• ISSNs: 1748-0221

Abstract

Abstract: Krypton-85 is an anthropogenic beta-decaying isotope which produces low energy backgrounds in dark matter and neutrino experiments, especially those based upon liquid xenon. Several technologies have been developed to reduce the Kr concentration in such experiments. We propose to augment those separation technologies by first adding to the xenon an 85 Kr-free sample of krypton in an amount much larger than the natural krypton that is already present. After the purification system reduces the total Kr concentration to the same level, the final 85 Kr concentration will be reduced even further by the dilution factor. A test cell for measurement of the activity of various Kr samples has been assembled, and the activity of 25-year-old krypton has been measured. The measured activity agrees well with the expected activity accounting for the 85 Kr abundance of the earth's atmosphere in 1990 and the half-life of the isotope. Additional tests with a Kr sample produced in the year 1944 (before the atomic era) have been done in order to demonstrate the sensitivity of the test cell.