English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We study high-energy neutrino production in inner jets of radio-loud activegalactic nuclei (AGN), taking into account effects of external photon fieldsand the blazar sequence. We show that the resulting diffuse neutrino intensityis dominated by quasar-hosted blazars, in particular, flat spectrum radioquasars, and that PeV-EeV neutrino production due to photohadronic interactionswith broadline and dust radiation is unavoidable if the AGN inner jets areultrahigh-energy cosmic-ray (UHECR) sources. Their neutrino spectrum has acutoff feature around PeV energies since target photons are due to Ly$\alpha$emission. Because of infrared photons provided by the dust torus, neutrinospectra above PeV energies are too hard to be consistent with the IceCube dataunless the proton spectral index is steeper than 2.5, or the maximum protonenergy is $\lesssim100$ PeV. Thus, the simple model has difficulty inexplaining the IceCube data. For the cumulative neutrino intensity from blazarsto exceed $\sim{10}^{-8}~{\rm GeV}~{\rm cm}^{-2}~{\rm s}^{-1}~{\rm sr}^{-1}$,their local cosmic-ray energy generation rate would be $\sim10-100$ timeslarger than the local UHECR emissivity, but is comparable to the averagedgamma-ray blazar emissivity. Interestingly, future detectors such as theAskaryan Radio Array can detect $\sim0.1-1$ EeV neutrinos even in moreconservative cases, allowing us to indirectly test the hypothesis that UHECRsare produced in the inner jets. We find that the diffuse neutrino intensityfrom radio-loud AGN is dominated by blazars with gamma-ray luminosity of$\gtrsim10^{48}~{\rm erg}~{\rm s}^{-1}$, and the arrival directions of their$\sim1-100$ PeV neutrinos correlate with the luminous blazars detected byFermi.

Diffuse Neutrino Intensity from the Inner Jets of Active Galactic Nuclei: Impacts of External Photon Fields and the Blazar Sequence