Antimatter stars could be hiding in our galaxy
Antimatter is the strange and evil twin of ordinary matter, and it is believed to have been mostly banished from our universe. But could he still hide there in large groups, even as stars? Astronomers have now identified a few signals that could be proof of these “anti-stars”, and calculated how many of them might be lurking in our own galaxy.
As science fiction as it sounds, antimatter is very real. Simply put, it is exactly the same as ordinary (or baryonic) matter, except that it has the opposite charge. This means that when particles of matter and antimatter meet, the two annihilate each other in a burst of energy.
According to our best models for the universe, matter and antimatter should have been created in equal amounts in the Big Bang, but today matter seems to dominate the cosmos. Antimatter is only produced in trace amounts, in instruments like the Large Hadron Collider or by natural processes such as lightning, hurricanes, cosmic ray interactions, radioactive decay or jets. plasma from neutron stars and black holes.
So where has all the antimatter gone? It appears to have been almost completely removed from contact with ordinary matter – and we were just lucky that there was some extra matter left, otherwise the universe would be a very empty place.
But maybe the ratio isn’t as skewed as we thought. Theoretically, there is no reason why antimatter shouldn’t be able to form stars and galaxies, planets, and even life, as long as there is no regular matter nearby for it. destroy it. It’s an intriguing possibility, but extremely difficult to validate – after all, the anti-stars would shine like the rest.
However, they can turn out in other ways. Since it would be quite difficult for anti-stars to find themselves in a region of space completely devoid of regular matter, scientists could potentially spot these imposters thanks to flashes of gamma rays, emitted by the annihilation of particles of matter. thugs who wander too close.
And that’s exactly what astronomers looked for in a new study. The team analyzed 10 years of data from the Fermi Space Telescope, examining 5,787 gamma ray sources for those that could be anti-stars. However, many other objects also emit gamma rays, so the researchers focused on those that came from a single point and had a light spectrum similar to what one would expect from matter-antimatter annihilation.
Indeed, among these thousands of sources, the team found 14 that match the bill. This does not mean that they are anti-stars, of course – the team recognizes that they’re much more likely to be more well-known gamma-ray emitters like pulsars or black holes. But the possibility is there, at least.
From there, the team extrapolated to come up with an estimate of how many anti-stars there could reasonably be in our galaxy. They found that if the anti-stars are distributed like regular stars, and if they have no difference besides the charge (something that antimatter studies are still studying), we are looking for about an anti- star for 300,000 normal stars. The primordial anti-stars might also have a tendency to escape attention by hanging out in the huge halo sparse around the galaxy, the team says.
It’s an intriguing idea, and one that will require further study to find more evidence.
The research was published in the journal Physical examination D.