Search for Light Dark Matter with 259-day data in PandaX-4T

TL;DR

This paper reports on a search for light dark matter particles using PandaX-4T data, setting new constraints on interaction cross-sections and improving previous limits across various mass ranges and interaction types.

Contribution

The study provides the most stringent constraints to date on certain dark matter interactions in the specified mass ranges, utilizing new data from PandaX-4T with improved analysis techniques.

Findings

Established new upper limits on spin-independent dark matter-nucleon interactions.

Improved dark matter-electron scattering cross-section limits by factors of 1.5 and 9.3.

Set the most stringent constraints on specific dark matter interaction cross-sections in the 2.0-5.3 GeV/$c^2$ mass range.

Abstract

We present a search for light dark matter particles through their interactions with atomic electrons and nucleons, utilizing PandaX-4T data with an effective exposure of 1.04 tonne$\cdot$year for ionization-only data and 1.20 tonne$\cdot$year for paired data. Our analysis focuses on the energy range (efficiency$>$0.01) of approximately 0.33 to 3 keV for nuclear recoils, and from 0.04 to 0.39 keV for electronic recoils. We establish the most stringent constraints on spin-independent dark matter-nucleon interactions within a mass range of 2.5 to 5.0 GeV/$c^2$, spin-dependent neutron-only interactions within 2.0 to 5.3 GeV/$c^2$, and spin-dependent proton-only interactions within 2.0 to 3.8 GeV/$c^2$. Their corresponding limits at 3\,GeV/$c^2$ are $1.1 \times 10^{-43}$, $1.6 \times 10^{-38}$, and $5.6 \times 10^{-37}$\,cm$^2$, respectively. Additionally, our results improve the upper limits on the dark matter-electron scattering cross-section by a factor of 1.5 and 9.3 for heavy and light mediator scenarios respectively within 50 MeV/$c^2$ to 10 GeV/$c^2$, compared with previous best results.