Source of High-Energy Cosmic Rays Found in Distant Space

While the object examined by the science team seems unique at this time, lead author of the research argued that it may in fact be “the brightest member of a new population of supernova remnants that emit gamma rays reaching TeV energies.”

Using the data supplied by NASA’s Fermi Gamma-ray Space Telescope, astronomers have confirmed the remnant of a supernova explosion to be a source of high-energy cosmic ray protons.

According to a statement released by NASA, said remnant is designated G106.3+2.7 and sits about 2,600 light years away from our planet, in the constellation Cepheus.

“Theorists think the highest-energy cosmic ray protons in the Milky Way reach a million billion electron volts, or PeV energies,” said Ke Fang, assistant professor of physics at the University of Wisconsin, Madison and lead author of the new study published in Physical Review letters this week. “The precise nature of their sources, which we call PeVatrons, has been difficult to pin down.”

The object that attracted the researchers’ attention is a comet-shaped cloud that features a bright pulsar, J2229+6114, on one end – likely a product of the same supernova explosion that created the cloud.

“This object has been a source of considerable interest for a while now, but to crown it as a PeVatron, we have to prove it’s accelerating protons,” said study’s co-author Henrike Fleischhack from the Catholic University of America in Washington and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The catch is that electrons accelerated to a few hundred TeV can produce the same emission. Now, with the help of 12 years of Fermi data, we think we’ve made the case that G106.3+2.7 is indeed a PeVatron.”

Fang also remarked that, while G106.3+2.7 appears unique, it may turn out to be “the brightest member of a new population of supernova remnants that emit gamma rays reaching TeV energies.”

“More of them may be revealed through future observations by Fermi and very-high-energy gamma-ray observatories,” the researcher added.