Data from the Antarctica-based IceCube neutrino observatory have been examined by astrophysicists. The stream of high-energy neutrinos detected by the telescope was found to have a galactic origin, meaning it was born in the Milky Way, as it turned out. The MIPT news service announced the discovery. The Milky Way’s neutrino emission drew the attention of physicists from the Institute for Nuclear Research RAS (INR RAS), the Physical Institute RAS (PHIAN), the Moscow Institute of Physics and Technology (MIPT), and the Max Planck Society Institute for Radio Astronomy (MPIfR, Germany). The neutrino is a special elementary particle that virtually does not interact with matter as it goes through it without encountering any impediments.
Neutrino telescopes, which have only lately begun operation, have discovered high-energy neutrinos coming from space. Physicists from all over the world examine the data from three neutrino telescopes: the European KM3NeT, the Russian Baikal Neutrino Telescope (also known as the Baikal-GVD project), and the American IceCube. However, they have yet to detect radiation from our galaxy. Although theorists were confident that neutrinos might be produced by stars with strong magnetic fields, such as those from cosmic rays. Sergei Troitsky of the INR, a RAS member, says: “Recent events include the simultaneous detection of a galactic source flare by the Kover-2 facility (located at the Baksan Neutrino Observatory of the INR RAS) and the arrival of high energy neutrinos noted by IceCube. This was the initial proof that neutrinos do indeed originate from cosmic sources. However, one neutrino is not evidence. Just a coincidence, perhaps.”
A team of researchers claims in a recent report that they have discovered galactic neutrino emission. The study process is described by PhIAN’s Alexander Plavin, Ph.D.: “We wondered if more neutrinos arrive at Earth from the plane of the Galaxy than from other directions. We meticulously gathered every instance of a high-energy neutrino that was recorded throughout our 10 years of observations, and we discovered the Milky Way in them. In neutrino astrophysics, where there are many uncertainties and yet scant qualitative data, the confidence level of 99.996% is rather exceptional.
On the one hand, this fundamental finding was long anticipated, but on the other, it raised new issues. The neutrino Milky Way’s width resembles two lengths of the Big Dipper, despite neutrinos being concentrated in the galactic plane and not in a narrow band. This suggests that a significant portion of neutrinos are likely born not just in our Galaxy, but also close by. This needs to be resolved still.
“New, more contemporary neutrino experiments in the Northern Hemisphere – Baikal-GVD and KM3NeT – will soon permit a comparable analysis with their data and a more in-depth examination of the galactic center region,” writes RAS corresponding member Yuri Kovalev (PhIAN and MIPT). For us northerners, the center of the Galaxy is “from under their feet,” where neutrino telescopes record elementary particles. According to the IceCube and Baikal-GVD data, we can clearly state that the neutrino sky is not so straightforward and that sources from both galactic and extragalactic classes contribute significantly to the flux of astrophysical neutrinos.