Constraints on ultra-high energy neutrinos from optically thick astrophysical accelerators

Abstract

The Z-burst mechanism invoked to explain ultra-high energy cosmic rays is severely constrained by measurements of the cosmic gamma-ray background by EGRET. We discuss the case of optically thick sources and show that jets and hot spots of active galaxies cannot provide the optical depth required to suppress the photon flux. Other extragalactic accelerators (AGN cores and sites of gamma ray bursts), if they are optically thick, could be tested by future measurements of the secondary neutrino flux.

9 pages, 1 figure; v2: 10 pages, references added; experimental data on neutrino fluxes updated significantly; to be published in Astropart.Phys

References in corpus (5)

• BL Lacertae are probable sources of the observed ultra-high energy cosmic rays
• Determination of absolute neutrino masses from Z-bursts
• Evidence for a connection between the gamma-ray and the highest energy cosmic-ray emissions by BL Lacertae objects
• Correlation function of ultra-high energy cosmic rays favors point sources
• Ultra-High Energy Cosmic Rays from Neutrino Emitting Acceleration Sources?

Cited by in corpus (11)

• Gravitational clustering of relic neutrinos and implications for their detection
• Ultra-High Energy Neutrino Fluxes: New Constraints and Implications
• Relic Neutrino Absorption Spectroscopy
• Bounds on Relic Neutrino Masses in the Z-burst Model
• Z-bursts from the Virgo cluster
• How to Detect Big Bang Relic Neutrinos?
• Physics with Cosmic Neutrinos, PeV to ZeV
• Multi-Messenger Astronomy: Cosmic Rays, Gamma-Rays, and Neutrinos
• Extremely energetic cosmic neutrinos and their impact on particle physics and cosmology
• The Mysteries of the Highest Energy Cosmic Rays
• Relic neutrino clustering and implications for their detection