In the realm of particle physics and astrophysics, researchers are continually pushing the boundaries of our understanding of the universe. Among them is Ye Xu, a scientist affiliated with the IceCube Neutrino Observatory, who has been delving into the mysteries of dark matter and its potential interactions with ordinary matter.
Xu’s recent research focuses on the search for milli-charged particles (MCPs), a hypothetical type of particle that carries a tiny fraction of the charge of an electron. These particles are thought to be produced by the decay of heavy dark matter captured by the Earth. The study leverages the capabilities of the IceCube neutrino telescope, a massive detector buried deep within the Antarctic ice, to search for these elusive particles.
The research assumes that heavy dark matter, with a mass on the order of a trillion electron volts (TeV), could be captured by the Earth and subsequently decay into relativistic MCPs. These MCPs are modeled as massless hidden photons, which interact with nuclei through a running electromagnetic coupling constant. This interaction allows for the evaluation of the numbers and fluxes of expected MCPs at IceCube.
Xu also evaluated the background events from neutrinos, which are abundant in the universe and can mimic the signals of MCPs. By assuming that no MCP events are observed at IceCube over a period of 10 years, the study calculates the corresponding upper limits on MCP fluxes at a 90% confidence level. The results indicate that MCPs from the Earth’s core could be directly detected at energies around 1 TeV at IceCube when the square of the MCP charge fraction, ε, is between approximately 5.65×10^-5 and 1.295×10^-3.
Furthermore, the research rules out a new region in the MCP mass (m_MCP) versus charge fraction (ε) plane, specifically for MCP masses between 4 GeV and 100 GeV and charge fractions between 5.51×10^-2 and 0.612. This exclusion region is derived from 10 years of IceCube data, providing valuable constraints on the properties of MCPs.
While the practical applications of this research for the energy sector are not immediately apparent, the study contributes to our fundamental understanding of particle physics and the nature of dark matter. A deeper comprehension of these phenomena could potentially lead to advancements in energy technologies, particularly in areas such as nuclear energy and particle acceleration. The research was published in the journal Physical Review D, a prestigious publication in the field of particle physics.
This article is based on research available at arXiv.