Details

Autor(en) / Beteiligte

• Murase, Kohta
• Inoue, Yoshiyuki
• Dermer, Charles D.

Titel

Diffuse neutrino intensity from the inner jets of active galactic nuclei: Impacts of external photon fields and the blazar sequence

Ist Teil von

• Physical review. D, Particles, fields, gravitation, and cosmology, 2014-07, Vol.90 (2), Article 023007

Erscheinungsjahr

2014

Link zum Volltext

Quelle

PROLA

Beschreibungen/Notizen

• We study high-energy neutrino production in inner jets of radio-loud active galactic nuclei (AGN), taking into account effects of external photon fields and the blazar sequence. We show that the resulting diffuse neutrino intensity is dominated by quasar-hosted blazars, in particular, flat spectrum radio quasars, and that PeV-EeV neutrino production due to photohadronic interactions with broadline and dust radiation is unavoidable if the AGN inner jets are ultrahigh-energy cosmic-ray (UHECR) sources. Their neutrino spectrum has a cutoff feature around PeV energies since target photons are due to Ly alpha emission. Because of infrared photons provided by the dust torus, neutrino spectra above PeV energies are too hard to be consistent with the IceCube data unless the proton spectral index is steeper than 2.5, or the maximum proton energy is [lap] 100 PeV. Thus, the simple model has difficulty in explaining the IceCube data. For the cumulative neutrino intensity from blazars to exceed ~ 10 super(-8) GeV cm super(-2) s super(-1) sr super(-1), their local cosmic-ray energy generation rate would be ~ 10-100 times larger than the local UHECR emissivity but is comparable to the averaged gamma -ray blazar emissivity. Interestingly, future detectors such as the Askaryan Radio Array can detect ~ 0.1-1 EeV neutrinos even in more conservative cases, allowing us to indirectly test the hypothesis that UHECRs are produced in the inner jets. We find that the diffuse neutrino intensity from radio-loud AGN is dominated by blazars with gamma -ray luminosity of [gap] 10 super(-48) erg s super(-1), and the arrival directions of their ~ 1-100 PeV neutrinos correlate with the luminous blazars detected by Fermi.