Dark matter could create dark dwarfs at the center of the Milky Way

Dark Matter is one of the most confusing mysteries in nature. It maintains particle physicists at night and cosmologists stuck to their supercalculator simulations. We know it’s real because its mass prevents galaxies from collapsing. But we don’t know what it is.

Dark Matter does not like others and may prefer his own business. Although he does not seem to interact with the regular Baryonic material, he could possibly react with himself and the auto-nihilat. It needs a closely packaged environment to do this, which can lead to a way in which astrophysicists can finally detect it.

New theoretical research describes how it could happen and indicates that under-steel objects, mainly brown dwarfs, could host the process. Research is entitled “Dark Nwarfs: Dark Matter-Awed Objects awaiting discovery at the Galactic Center”, and it is published in the Journal of Cosmology and Astroparticle Physics. The main author is Djuna Croon, theoretical physicist and assistant professor at the Institute of Phenomenology of Particle Physics in the Physics Department of the University of Durham.

The brown dwarfs are larger sub-species than planets but not massive enough to trigger the fusion of hydrogen. When the brown dwarfs are formed, they follow the same process as the stars. But unfortunately for them, their gas accretion blocks and reigns their growth. They cannot become massive enough to trigger the fusion of hydrogen and are sentenced to a lifespan of weakness. They generate heat by briefly merging the Deuterium and by the gravitational contraction, but they never shine like the stars.

In terms of light, they are darker than white dwarfs but slightly more shiny than gas giants like Jupiter. Over time, brown dwarfs cool and become darker and darker. Brown dwarfs are notoriously difficult to detect due to their weakness and low mass.

Croon and his co-researchers suggest that the annihilation of dark matter could make brown dwarfs detectable. Black matter particles can be their own anti-praticles and can be an end to each other when their density is high. According to E = MC²Their annihilation converts their mass into energy and produces particles from the standard model such as photons, electrons and positrons.

“The dark matter interacts gravitally, it could therefore be captured by stars and accumulate inside,” said co-author Jeremy Sakstein in a press release. “If this happens, he could also interact with himself and destroy, releasing energy that heats the star.” Sakstein is a professor of physics at the University of Hawaii.

There is more dark matter near the galactic center, and the authors think that this is where enough can accumulate in brown dwarfs for self-annihilation. When this happens, this creates another type of under-species object: the dark dwarfs.

“These objects collect the dark matter which helps them to become a dark dwarf. The more dark matter you, the more you can capture,” explains Sakstein. “And the more dark matter is found inside the star, the more energy there will be through its annihilation.”

There are many candidate particles for dark matter. One of them weakly interacts massive particles (Wimp), and this theoretical model only works if the Wimp are indeed what dark matter is. “For black dwarves to exist, dark matter must be made of Wimp, or any heavy particle that interacts with itself to produce visible matter,” explains Sakstein.

If we can detect these dark dwarfs, we essentially detect dark matter. Detection is based on lithium-7, an isotope with natural lithium which is the most abundant and stable of all the isotopes of lithium. The normal brown dwarfs would exhaust their lithium-7 while the dark dwarves would keep it.

“The DDs are physically distinct from brown / red dwarfs in several ways,” write the authors. They are slightly more massive and are mainly powered by DM annihilation, with an additional stable fusion component of hydrogen. Their luminosities, rays and effective temperatures are constant over time. The authors also explain that these dark dwarfs would keep their lithium while it is exhausted by nuclear combustion in the brown dwarfs.

“The lithium test is a main method to confirm that an object is a brown dwarf,” write the researchers. Astronomers use lithium lines in stellar spectra to draw the central temperature stories of brown dwarfs and young stars and to determine in which evolutionary era in which they are.

“The detection of lithium-7 in heavier objects than the lithium combustion limit would provide evidence of the existence of DM heating,” write the researchers in their article. “One consequence of this is that DDs can be identified by their improved lithium abundance despite a relatively large mass and a stellar age.” They also show that the amount of lithium preserved over time depends on the densities of mass and black matter.

“There were a few markers, but we suggested lithium-7 because it would really be a unique effect,” said Sakstein. Ordinary stars quickly consume lithium-7. “So, if you could find an object that looked like a dark dwarf, you can seek the presence of this lithium because it would not be there if it was a brown dwarf or a similar object.”

The dark dwarves are extremely cold objects, and although the JWST can detect them, there may be another way, according to Sakstein. “The other thing you might do is to look at a whole population of objects and ask, in a statistical way, if it is better described by having a subpopulation of dark dwarfs or not.”

Finding dark dwarfs would greatly contribute to answering the question on the nature of dark matter. If we could detect dark dwarfs, it would reinforce the idea that dark matter is Wimp.

“With candidates for clear dark matter, something like an axion, I don’t think you could get something like a dark dwarf,” said Sakstein. “They do not accumulate inside the stars. If we manage to find a dark dwarf, it would provide convincing evidence that dark matter is heavy and interact strongly with itself, but only weakly with the standard model.

“The observation of a dark dwarf would not tell us in a conclusive way that dark matter is a wimp, but it would mean that it is a wimp or something which, for all useful purposes, behaves like a wimp.”