Resolving XENON Excess With Decaying Cold Dark Matter

TL;DR

This paper introduces a decaying cold dark matter model to explain the XENON1T electron recoil excess, matching observed energies and rates while remaining consistent with existing experimental constraints.

Contribution

It presents a novel decaying dark matter framework that accounts for the XENON1T excess without conflicting with other cosmological and detection limits.

Findings

Model explains the 2.5 keV recoil peak

Dark matter with 10-200 MeV mass fits data

Model remains consistent with cosmological constraints

Abstract

We propose a decaying cold dark matter model to explain the excess of electron recoil observed at the XENON1T experiment. In this scenario, the daughter dark matter from the parent dark matter decay easily obtains velocity large enough to saturate the peak of the electron recoil energy around 2.5 keV, and the observed signal rate can be fulfilled by the parent dark matter with a mass of order 10-200 MeV and a lifetime larger than the age of Universe. We verify that this model is consistent with experimental limits from dark matter detections, Cosmic Microwave Background and Large Scale Structure experiments.