An artist's interpretation of a neutrino interaction at the IceCube Neutrino Observatory. Inset is a plot of the spectral fit to the flux of cosmic neutrinos, illustrating the break in the spectrum. Credit: Brad Sherman/IceCube Collaboration. A new study published in Physical Review Letters by the IceCube Collaboration reports evidence that the energy spectrum of astrophysical neutrinos is not a simple straight line. Astrophysical neutrinos are tiny, nearly massless particles produced when high-energy cosmic rays interact with matter or radiation near sources such as active galactic nuclei, gamma-ray bursts, and supernova remnants. Because they barely interact with anything, they travel from the edges of the observable universe in straight lines, carrying information about the environments that produced them. Analyzing more than a decade of data, the study found a break in the spectrum near 30 TeV, comparable to the energies seen at the Large Hadron Collider.…