Neutron Stars prove to be a crucial tool in quest to unravel dark matter
Melbourne, Australia (SPX) Apr 08, 2024 -
In a new study, scientists at the University of Melbourne's ARC Centre of Excellence for Dark Matter Particle Physics have made significant advancements in understanding dark matter by studying neutron stars, potentially unlocking new methods to detect this elusive component of our universe.Recent findings, detailed in The Journal of Cosmology and Astroparticle Physics, suggest that when dark matter particles collide and annihilate within the dense core of cold, dormant neutron stars, they can release sufficient energy to rapidly heat these stars. Contrary to previous beliefs that such processes could extend beyond the universe's lifespan, this energy deposition now appears to occur within mere days.
Professor Nicole Bell, a leading researcher in the project, emphasized the importance of this discovery. "Dark matter constitutes about 85% of the universe's matter, yet remains invisible as it does not interact with light. Traditionally, its presence is inferred through gravitational effects on visible celestial bodies. Neutron stars, with their intense gravitational fields, provide a natural laboratory for trapping and accumulating dark matter over astronomical timescales, making them excellent candidates for dark matter research," explained Professor Bell.
Neutron stars emerge from the gravitational collapse of supermassive stars and are characterized by their extreme density, with masses comparable to the Sun but confined to a sphere just 20 kilometers across. This density threshold is just shy of that required to form black holes, making neutron stars the denser objects in the universe that we can directly observe.
Michael Virgato, a PhD candidate at the University of Melbourne, discussed the practical implications of these findings. "As dark matter particles accumulate within a neutron star, they lose energy through collisions with neutrons, becoming trapped. This process heats the neutron star, potentially to temperatures observable with future astronomical technology. If the energy transfer is sufficiently rapid, it might even catalyze the neutron star's collapse into a black hole," he noted.
This mechanism of heating and potential collapse provides a novel method to detect dark matter indirectly. Observing these thermal changes in neutron stars could reveal new insights into the interactions between dark and ordinary matter. Such observations could be crucial for constructing a more comprehensive model of the universe's fundamental components.
The research underscores the synergy between theoretical predictions and experimental observations in advancing our understanding of dark matter. While Earth-based experiments continue to face challenges due to the technical limitations of constructing large enough detectors, celestial bodies like neutron stars offer a promising alternative for studying dark matter in natural settings.
"This breakthrough shows that dark matter may influence observable phenomena in ways we can detect and measure," said Virgato. "By studying neutron stars, we not only unravel the mysteries of these fascinating objects but also use them as tools to probe the far more elusive nature of dark matter."
As the scientific community continues to explore these phenomena, the insights gained from neutron stars are likely to play a major role in shaping our understanding of the cosmos. The detection of dark matter through such indirect means could potentially answer some of the most pressing questions in astrophysics and cosmology.
Research Report:Thermalization and annihilation of dark matter in neutron stars