The NEWS-G direct detection experiment uses spherical proportional counters to search for light dark matter candidates. New results from a 10 day physics run with a $135\,\mathrm{ cm}$ in diameter spherical proportional counter at the Laboratoire Souterrain de Modane are reported. The target consists of $114\,\mathrm{ g}$ of methane, providing sensitivity to dark matter spin-dependent coupling to protons. New constraints are presented in the mass range $0.17$ to $1.2\,\mathrm{ GeV/c^2}$, with a 90% confidence level cross-section upper limit of $30.9\,\mathrm{ pb}$ for a mass of $0.76\,\mathrm{ GeV/c^2}$.
Categories: hep-ex astro-ph.CO