Constraining Dark Matter Models with a Light Mediator from CDEX-10 Experiment at China Jinping Underground Laboratory

TL;DR

This paper reports on a search for light-mediator dark matter using germanium detector data from CDEX-10, setting new limits on interaction cross sections and constraining specific self-interacting dark matter models.

Contribution

It provides the first experimental constraints on light-mediator dark matter in the 2-5 GeV mass range using CDEX-10 data, including limits on a photon-coupled self-interacting model.

Findings

Excluded new parameter space for 2-5 GeV dark matter mass.

Set upper limits on DM-nucleon cross sections at 90% confidence level.

Constrained self-interacting dark matter models with light mediators.

Abstract

We search for nuclear recoil signals of dark matter models with a light mediator using data taken from a p-type point-contact germanium detector of the CDEX-10 experiment at the China Jinping Underground Laboratory. The 90% confidence level upper limits on the DM-nucleon interaction cross section from 205.4 kg-day exposure data are derived, excluding new parameter space in 2~5 GeV DM mass when the mediator mass is comparable to or lighter than the typical momentum transfer. We further interpret our results to constrain a specific self-interacting dark matter model with a light mediator coupling to the photon through kinetic mixing, and set experimental limits on the model parameter region favored by astrophysical observations.