Any substance which interacts mostly via gravity with visible matter can be called dark matter. New research now says that it could be that the dark matter is responsible for the peculiar observation of gamma rays in the core of our solar system.
It was discovered a decade ago that the center of the Milky Way is sending too many gamma rays towards Earth. Dark matter was considered to be responsible for this surplus, but after collecting more data, the idea faded away as the cause was thought to be something more ordinary. The initial impression might, however, come back to life as a new analysis could drop the stick in favor of dark matter theory.
Why Could Dark Matter Be The Cause
Rebecca Leane, a postdoctoral researcher at the Center for Theoretical Physics at MIT, proved that a contribution of gamma rays from dark matter might be wrongly interpreted as coming from “point sources,” which are objects similar to stars in the sky, probably pulsars.
She explained: “If it turns out that the signal is dark matter, that’s huge for our understanding of the universe. We know that dark matter makes up most of the universe, but we don’t have much of an idea of what it is… if there’s a dark matter signal, that would have a massive impact, and getting to the bottom of it would be very interesting.”
The scientists have conducted a test by sending a fake signal similar to the effect of dark matter into the real data; the model wrongly assigned the dark matter signal to point sources.
“This suggests that the data are mismodelled in some way, and that dark matter may be the dominant contribution to the galactic center excess after all – though this does not constitute positive evidence for dark matter, and the [excess] could still be composed mainly of point sources,” the authors write in the research already published in the journal Physical Review Letters.
Their discovery basically demonstrates a flaw in the two papers published back in 2016 that seemed to favor an undiscovered population of pulsars as a better option for the data, therefore excluding the dark matter out of the equation.
Reactions To The New Discovery
These discoveries are animating dark matter experts. Dan Hooper, senior scientist and the chief of the Theoretical Astrophysics Group at the Fermi National Accelerator Laboratory, said: “I’m approximately as bullish on the dark matter interpretation on this signal now as I’ve ever been.”
Mariangela Lisanti, a Princeton professor who worked on the 2016 paper with Slatyer, also said that it’s crucial to analyze all the uncertainties when searching for dark matter, “especially one focusing on gamma rays from the Milky Way’s galactic center.”
“It’s a challenging problem, but so far, our results remain generally consistent with the conclusions of the original 2016 study,” she says. It’s undoubtedly tough to get accurate data concerning the vast space that surrounds us, but in the end, more evidence has to appear. Scientists hope it will be discovered before the true identity of the origin of the mysterious excess reveals itself.