Search for Milli-Charged Particles from the Sun at IceCube

TL;DR

This paper investigates the potential detection of milli-charged particles originating from the Sun using IceCube, setting new limits on their flux and parameter space based on 6 years of data.

Contribution

It introduces a model for MCPs interacting with nuclei in IceCube and establishes new upper limits on MCP fluxes and parameter space from observational data.

Findings

No MCP events observed in 6 years at IceCube.

Set upper limits on MCP fluxes at 90% confidence level.

Ruled out a new region in MCP mass and charge parameter space.

Abstract

It is assumed that heavy dark matter particles $\phi$ with O(TeV) mass captured by the Sun may decay to relativistic light milli-charged particles (MCPs). These MCPs could be measured by the IceCube detector. The massless hidden photon model was taken for MCPs to interact with nuclei, so that the numbers and fluxes of expected MCPs and neutrinos may be evaluated at IceCube. Based on the assumption that no events are observed at IceCube in 6 years, the corresponding upper limits on MCP fluxes were calculated at 90\% C. L.. These results indicated that MCPs could be directly detected in the secondaries' energy range O(100GeV)-O(10TeV) at IceCube, when $\epsilon^2\gtrsim10^{-10}$. And a new region of 0.6 MeV < $m_{MCP}$ < 10 MeV and $6\times10^{-6}$ < $\epsilon$ $\lesssim$ $10^{-4}$ is ruled out in the $m_{MCP}$-$\epsilon$ plane with 6 years of IceCube data.