Nature 520, 266 (16 April 2015) doi:10.1038/520266b
Two of the most energetic neutrinos detected by a telescope in the Antarctic may have come from the cores of distant galaxies.
Neutrinos are stable and can travel far in space, so they could shed light on distant astrophysical and galactic objects. The Antarctic telescope IceCube picked up signs of neutrinos in 2011 and 2012 that were the first ever measured with energies of 1 petaelectronvolt (1 × 1015 electronvolts), suggesting a powerful source such as a blazar — a type of high-energy galaxy.
A team led by Clancy James of the University of Erlangen and Matthias Kadler of the University of Würzburg, both in Germany, studied six years of data from the underwater ANTARES neutrino telescope off the coast of Toulon, France, scanning six blazars for further neutrinos. The two blazars considered to be the best candidates each yielded events that were consistent with the signature of a neutrino, suggesting that they could be the sources of the IceCube neutrinos.
ANTARES constrains a blazar origin of two IceCube PeV neutrino events, A&A 576, L8 (2015)