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New Experiments With Spheres-Gas (NEWS-G) is a direct dark matter detection experiment using SphericalProportional Counters (SPCs) with light noble gases to search for low-mass Weakly Interacting Massive Particles (WIMPs). We report the results from the first physics run taken at the Laboratoire Souterrain de Modane (LSM) with SEDINE, a 60 cm diameter prototype SPC operated with a mixture of Ne + CH 4 (0.7 %) at 3.1 bars for a total exposure of 9.7 kg · days. New constraints are set on the spin-independent WIMP-nucleon scattering cross-section in the sub-GeV/c 2 mass region. We exclude cross-sections above 4.4 × 10 −37 cm 2 at 90 % confidence level (C.L.) for a 0.5 GeV/c 2 WIMP. The competitive results obtained with SEDINE are promising for the next phase of the NEWS-G experiment: a 140 cm diameter SPC to be installed at SNOLAB by summer 2018.

The PICASSO dark matter search experiment operated an array of 32 superheated droplet detectors containing 3.0 kg of C 4 F 10 and collected an exposure of 231.4 kgd at SNOLAB between March 2012 and January 2014. We report on the final results of this experiment which includes for the first time the complete data set and improved analysis techniques including acoustic localization to allow fiducialization and removal of higher activity regions within the detectors. No signal consistent with dark matter was observed. We set limits for spin-dependent interactions on protons of σ SD p = 1.32 × 10 −2 pb (90% C.L.) at a WIMP mass of 20 GeV/c 2 . In the spin-independent sector we exclude cross sections larger than σ SI p = 4.86 × 10 −5 pb (90% C.L.) in the region around 7 GeV/c 2 . The pioneering efforts of the PICASSO experiment have paved the way forward for a next generation detector incorporating much of this technology and experience into larger mass bubble chambers.

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