IceCube Proves Its Neutrino Telescope Works

The IceCube Neutrino Observatory's latest improvements have brought it to the point where it has started to function as a genuine neutrino telescope as intended. A new paper to be released tomorrow documents its successful test run.

[T]he IceCube Neutrino Observatory has produced an image of the Milky Way using neutrinos—tiny, ghostlike astronomical messengers. In an article to be published tomorrow, June 30, in the journal Science, the IceCube Collaboration, an international group of over 350 scientists, presents evidence of high-energy neutrino emission from the Milky Way. 

The high-energy neutrinos, with energies millions to billions of times higher than those produced by the fusion reactions that power stars, were detected by the IceCube Neutrino Observatory, a gigaton detector operating at the Amundsen-Scott South Pole Station. . . . 

[U]nlike the case for light of any wavelength, in neutrinos, the universe outshines the nearby sources in our own galaxy. . . . Interactions between cosmic rays—high-energy protons and heavier nuclei, also produced in our galaxy–and galactic gas and dust inevitably produce both gamma rays and neutrinos. 

Given the observation of gamma rays from the galactic plane, the Milky Way was expected to be a source of high-energy neutrinos. “A neutrino counterpart has now been measured, thus confirming what we know about our galaxy and cosmic ray sources. . . 

“The improved methods allowed us to retain over an order of magnitude more neutrino events with better angular reconstruction, resulting in an analysis that is three times more sensitive than the previous search,” . . . . The dataset used in the study included 60,000 neutrinos spanning 10 years of IceCube data, 30 times as many events as the selection used in a previous analysis of the galactic plane using cascade events. These neutrinos were compared to previously published prediction maps of locations in the sky where the galaxy was expected to shine in neutrinos.

From the IceCube Press Release at its website.