Search for light dark matter with NEWS-G

TL;DR

The NEWS-G experiment searches for light dark matter particles in the 0.1-10 GeV mass range using a spherical proportional counter with hydrogen, helium, and neon gases, providing new upper limits on interaction cross-sections.

Contribution

This work introduces a new large detector and improved instrumentation for detecting light dark matter, extending previous limits and capabilities.

Findings

Set a 90% CL upper limit of 4.4x10^{-37} cm^2 on cross-section for 0.5 GeV dark matter.

Developed a new 140 cm diameter detector with enhanced shielding.

Presented recent detector instrumentation improvements.

Abstract

The NEWS-G collaboration is searching for light dark matter candidates using a spherical proportional counter. Light gases, such as hydrogen, helium, and neon, are used as targets, providing access in the 0.1-10 GeV mass range. First results obtained with SEDINE, a 60 cm in diameter detector, in the Underground Laboratory of Modane yielded a 90% confidence level upper limit of 4.4x 10^{37} cm^2 on the nucleon-dark matter interaction cross-section for a candidate with 0.5 GeV mass. Recent developments in several aspects of the detector instrumentation are presented, along with the construction of a new, 140 cm in diameter, detector with new compact shielding.