First results from the NEWS-G direct dark matter search experiment at the LSM

Q. Arnaud , D. Asner , J.-P. Bard (1) , A. Brossard (1) , B. Cai , M. Chapellier , M. Clark , E.C. Corcoran , T. Dandl , A. Dastgheibi-Fard (2) , K. Dering , P. Di Stefano , D. Durnford , G. Gerbier , I. Giomataris (1) , P. Gorel , M. Gros (1) , O. Guillaudin (3) , E.W. Hoppe , A. Kamaha , I. Katsioulas (1) , D.G. Kelly , R.D. Martin , J. Mcdonald , J.-F. Muraz (3) , J.-P. Mols (1) , X.-F. Navick (1) , T. Papaevangelou (1) , F. Piquemal (2) , S. Roth , D. Santos (3) , I. Savvidis , A. Ulrich , F. Vazquez de Sola Fernandez , M. Zampaolo (2)

1 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
2 LSM - UMR 6417 - Laboratoire Souterrain de Modane
3 LPSC - Laboratoire de Physique Subatomique et de Cosmologie

New Experiments With Spheres-Gas (NEWS-G) is a direct dark matter detection experiment using Spherical Proportional 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 9.6 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 4.4×10−37cm2 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.

Mots clés: Spherical Proportional Counter; dark matter; direct detection; low-mass WIMPs; Spherical proportional counter; Dark matter; Direct detection; Low-mass WIMPs; dark matter: direct detection; WIMP nucleon: scattering; WIMP; gas; mass; spin; cross section; S030DI1; S030DI5

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Astrophysique [astro-ph]

Q. Arnaud, D. Asner, J.-P. Bard, A. Brossard, B. Cai, et al.. First results from the NEWS-G direct dark matter search experiment at the LSM. Astropart.Phys., 2018, 97, pp.54-62. ⟨10.1016/j.astropartphys.2017.10.009⟩. ⟨hal-01645358⟩