Shedding Light on Mirror Dark Matter Using CDEX

TL;DR

This paper uses data from the CDEX experiment to set new limits on mirror dark matter interactions mediated by photon mixing, significantly improving sensitivity over previous experiments and exploring new parameter space.

Contribution

It provides the first constraints on mirror dark matter using CDEX data and projects future sensitivity improvements with CDEX-300, surpassing existing bounds.

Findings

CDEX-10 constrains kinetic mixing parameter to < 2 x 10^{-10} for 10-56 GeV mirror nuclei.

CDEX-300 projections reach sensitivity of < 3.75 x 10^{-11}, surpassing LUX and positronium decay bounds.

Results demonstrate CDEX-300's potential to probe mirror dark matter models effectively.

Abstract

Mirror dark matter, a hidden-sector counterpart to the Standard Model with identical particle content, could be detectable through photon-mirror-photon kinetic mixing $(\epsilon)$. We present new constraints from CDEX-10 low-energy recoil data, establishing $\epsilon < 2 \times 10^{-10}$ for mirror nuclear dark matter in the 10--56 GeV mass range. Projections for CDEX-300 (with 95 days of exposure) show significantly improved sensitivity, reaching $\epsilon < 3.75 \times 10^{-11}$ for a local mirror halo temperature below 0.3 keV, surpassing existing constraints from LUX and positronium decays. These results demonstrate CDEX-300's unique capability to probe kinetic-mixing parameter space, providing stringent constraints on mirror dark matter models.