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

## TL;DR

The NEWS-G experiment uses spherical proportional counters with light noble gases to search for low-mass WIMPs, providing new constraints on dark matter particle interactions from initial results at LSM.

## Contribution

This paper presents the first physics results from the NEWS-G experiment using a spherical proportional counter with neon and methane, setting new limits on low-mass WIMP interactions.

## Key findings

- Excluded WIMP-nucleon cross-sections above 4.4 x 10^-37 cm^2 at 0.5 GeV/c^2
- Demonstrated the detector's capability to set competitive constraints
- Laid groundwork for a larger detector at SNOLAB

## Abstract

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 $\mathrm{Ne}+\mathrm{CH}_{4}$ (0.7 %) at 3.1 bars for a total exposure of $9.7\;\mathrm{kg\cdot days}$. New constraints are set on the spin-independent WIMP-nucleon scattering cross-section in the sub-$\mathrm{GeV/c^2}$ mass region. We exclude cross-sections above $4.4 \times \mathrm{10^{-37}\;cm^2}$ at 90 % confidence level (C.L.) for a 0.5 $\mathrm{GeV/c^2}$ 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.