title: Hidden Cosmic-Ray Accelerators as an Origin of TeV-PeV Cosmic Neutrinos.
abstract: The latest IceCube data suggest that the all-flavor cosmic neutrino flux may be as large as 10^{-7}  GeV cm^{-2} s^{-1} sr^{-1} around 30 TeV. We show that, if sources of the TeV-PeV neutrinos are transparent to γ rays with respect to two-photon annihilation, strong tensions with the isotropic diffuse γ-ray background measured by Fermi are unavoidable, independently of the production mechanism. We further show that, if the IceCube neutrinos have a photohadronic (pγ) origin, the sources are expected to be opaque to 1-100 GeV γ rays. With these general multimessenger arguments, we find that the latest data suggest a population of cosmic-ray accelerators hidden in GeV-TeV γ rays as a neutrino origin. Searches for x-ray and MeV γ-ray counterparts are encouraged, and TeV-PeV neutrinos themselves will serve as special probes of dense source environments.
authors.affiliation: Center for Particle and Gravitational Astrophysics; Department of Physics; Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.|Institute for Advanced Study, Princeton, New Jersey 08540, USA.
authors.forename: Kohta
authors.initials: K
authors.lastname: Murase
authors.affiliation: Osservatorio Astronomico di Roma, I-00040 Monte Porzio Catone, Italy.|Department of Physics and Optical Engineering, ORT Braude College, Karmiel 21982, Israel.
authors.forename: Dafne
authors.initials: D
authors.lastname: Guetta
authors.affiliation: Wisconsin IceCube Particle Astrophysics Center (WIPAC) and Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
authors.forename: Markus
authors.initials: M
authors.lastname: Ahlers