I will discuss the recent observation of TeV to PeV neutrinos by the IceCube Cherenkov telescope in the context of multi-messenger astronomy. The corresponding energy range of hadronic gamma-rays is not directly accessible by extragalactic gamma-ray astronomy due to interactions with cosmic radiation backgrounds. Nevertheless, the isotropic sub-TeV gamma-ray background observed by Fermi-LAT contains indirect information from secondary emission produced in electromagnetic cascades and constrains hadronic emission scenarios. On the other hand, observation of PeV gamma-rays would provide a smoking-gun signal for Galactic emission. Interestingly, the overall energy density of the observed neutrino flux is close to a theoretical limit for neutrino production in the sources of ultra-high energy cosmic rays and might indicate a common origin of these phenomena. I will highlight various multi-messenger relations involving cosmic neutrinos and proposed source scenarios.
|Collaboration||-- not specified --|
|Registration number following "ICRC2015-I/"||374|