The highest energy neutrinos: first evidence for cosmic origin

Understand

Developments in neutrino astronomy have been to a great extent motivated by the search for the sources of the cosmic rays, leading at a very early stage to the concept of a cubic kilometer neutrino detector.

• Almost four decades later such an instrument, IceCube, is taking data and has produced the first evidence for a flux of high-energy neutrinos of cosmic origin.
• After a brief review of the history of the field, we will introduce IceCube and describe the first analysis of data taken with the completed instrument.
• The atmospheric neutrino flux cannot accommodate an excess of 28 neutrinos observed with energies above 60 TeV.