Discovery of underground argon with low level of radioactive 39Ar and possible applications to WIMP dark matter detectors

D. Acosta-Kane, R. Acciarri, O. Amaize, M. Antonello, B. Baibussinov, M. Baldo Ceolin, C. J. Ballentine, R. Bansal, L. Basgall, A. Bazarko, P. Benetti, Jay Burton Benziger, A. Burgers, Frank Calaprice, E. Calligarich, M. Cambiaghi, N. Canci, F. Carbonara, M. Cassidy, F. CavannaS. Centro, A. Chavarria, D. Cheng, A. G. Cocco, P. Collon, F. Dalnoki-Veress, E. de Haas, F. Di Pompeo, G. Fiorillo, F. Fitch, V. Gallo, Cristiano Galbiati, M. Gaull, S. Gazzana, L. Grandi, A. Goretti, R. Highfill, T. Highfill, T. Hohman, Al Ianni, An Ianni, A. LaCava, M. Laubenstein, H. Y. Lee, M. Leung, B. Loer, H. H. Loosli, B. Lyons, D. Marks, K. McCarty, G. Meng, C. Montanari, S. Mukhopadhyay, A. Nelson, O. Palamara, L. Pandola, F. Pietropaolo, T. Pivonka, A. Pocar, R. Purtschert, A. Rappoldi, G. Raselli, F. Resnati, D. Robertson, M. Roncadelli, M. Rossella, C. Rubbia, J. Ruderman, R. Saldanha, C. Schmitt, R. Scott, E. Segreto, A. Shirley, A. M. Szelc, R. Tartaglia, T. Tesileanu, S. Ventura, C. Vignoli, Catherine Katerina Visnjic, R. Vondrasek, A. Yushkov

Research output: Contribution to journalArticlepeer-review

53 Scopus citations


We report on the first measurement of 39Ar in argon from underground natural gas reservoirs. The gas stored in the US National Helium Reserve was found to contain a low level of 39Ar. The ratio of 39Ar to stable argon was measured to be ≤ 4 × 10- 17 (84% C.L.), less than 5% the value in atmospheric argon (39 Ar / Ar = 8 × 10- 16). The total quantity of argon currently stored in the National Helium Reserve is estimated at 1000 tons. 39Ar represents one of the most important backgrounds in argon detectors for WIMP dark matter searches. The findings reported demonstrate the possibility of constructing large multi-ton argon detectors with low radioactivity suitable for WIMP dark matter searches.

Original languageEnglish (US)
Pages (from-to)46-51
Number of pages6
JournalNuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
Issue number1
StatePublished - Mar 11 2008

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Instrumentation


  • Cryogenic noble gases
  • Dark matter
  • Low background detectors


Dive into the research topics of 'Discovery of underground argon with low level of radioactive 39Ar and possible applications to WIMP dark matter detectors'. Together they form a unique fingerprint.

Cite this