The DarkSide collaboration is an international affiliation of universities and labs seeking to directly detect dark matter in the form of weakly interacting massive particles (WIMPs). The collaboration is building a series of noble liquid time projection chambers (TPCs) that are designed to be employed at the Gran Sasso National Laboratory in Assergi, Italy. The detector is filled with liquid argon from underground sources in order to exclude the radioactive isotope 39
Ar, which is makes up one in every 1015 (quadrillion) atoms in atmospheric argon. The Darkside-10 prototype was tested in 2012, and the Darkside-50 experiment has been operating since 2013.
Darkside-50 is operating with 46 kg of argon target mass. A 3 year run is planned and ton-scale expansion has been proposed.
Initial results using a month of running were reported in 2014. Spin-independent limits were set using 1422 kg×days of exposure to atmospheric argon. A cross section limit of 6952610000000000000♠6.1×10−44 cm2 for a 100 Gev WIMP was found.
The following institutions' physics departments include members of DarkSide:
Augustana College, USA
Black Hills State University, USA
Drexel University, USA
Fermi National Accelerator Laboratory, USA
The University of Chicago, USA
Princeton University, USA
Temple University, USA
University of Arkansas, USA
University of California at Los Angeles, USA
University of California at Davis, USA
University of Houston, USA
University of Massachusetts at Amherst, USA
Virginia Tech, USA
University College of London, GB
Institute of High Energy Physics, China
INFN - Laboratori Nazionali del Gran Sasso, Italy
INFN – Università degli Studi di Genova, Italy
INFN – Università degli Studi di Milano, Italy
INFN – Università degli Studi di Napoli, Italy
INFN – Università degli Studi di Perugia, Italy
Jagiellonian University, Cracow, Poland
Joint Institute for Nuclear Research, Dubna, Russia
Lomonosov Moscow State University, Russia
Institute for Nuclear Research of NASU, Kiev, Ukraine
RRC Kurchatov Institute, Russia
National Research Nuclear University, Moscow, Russia
Institute for Theoretical and Experimental Physics, Moscow, Russia
St. Petersburg Nuclear Physics Institute, Gatchina, Russia
D.Akimov et al., “Light Yield in DarkSide-10: a Prototype Two-phase Liquid Argon TPC for Dark Matter Searches” - 2012. - arXiv:1204.6218.
H.O. Back et al., “First Large Scale Production of Low Radioactivity Argon From Underground Sources” - 2012. – arXiv:1204.6024.
H.O. Back et al., “First Commissioning of a Cryogenic Distillation Column for Low Radioactivity Underground Argon”. - 2012. - arXiv:1204.6061.
J.Xu et al., “A Study of the Residual 39Ar Content in Argon from Underground Sources” - 2012. - arXiv:1204.6011.
A. Wright, P. Mosteiro, B. Loer and F. Calaprice, “A Highly Efficient Neutron Veto for Dark Matter Experiments”, Nuclear Instruments and Methods A 644, 18 (2011). - arXiv:1010.3609.
DarkSide Collaboration, “DarkSide-50 Proposal” (2008).
D. Acosta-Kane et al., “Discovery of underground argon with low level of radioactive 39Ar and possible applications to WIMP dark matter detectors”, Nuclear Instruments and Methods A 587, 46 (2008). - arXiv:0712.0381.