Limits on Light Weakly Interacting Massive Particles from the First 102.8 kg ${\times}$ day Data of the CDEX-10 Experiment

TL;DR

This paper reports the first results from the CDEX-10 experiment, setting new limits on light WIMP interactions using a germanium detector with 102.8 kg day exposure, extending sensitivity to WIMPs as light as 2 GeV/c².

Contribution

First results from CDEX-10 with improved limits on light WIMP-nucleon cross sections at low WIMP masses.

Findings

Set upper limits of 8×10⁻⁴² cm² for spin-independent interactions at 5 GeV/c²

Set upper limits of 3×10⁻³⁶ cm² for spin-dependent interactions at 5 GeV/c²

Extended sensitivity to WIMP masses down to 2 GeV/c²

Abstract

We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8 $\times 10^{-42}$ and 3 $\times 10^{-36}$ cm$^{2}$ at a 90\% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass ($m_{\chi}$) of 5 GeV/${c}^2$ are achieved. The lower reach of $m_{\chi}$ is extended to 2 GeV/${c}^2$.