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 Tools annual

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 Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The great power offered by photoionization models of Active Galactic Nuclei(AGN) emission-line regions has long been mitigated by the fact that verylittle is known about the spectral energy distribution (SED) between the Lymanlimit, where intervening absorption becomes a problem, and 0.3 keV, where softx-ray observations become possible. The emission lines themselves can, to somedegree, be used to probe the SED, but only in the broadest terms. This paperemploys a new generation of theoretical SEDs which are internallyself-consistent, energy-conserving, and tested against observations, to inferproperties of the emission-line regions. The SEDs are given as a function ofthe Eddington ratio, allowing emission-line correlations to be investigated ona fundamental basis. We apply the simplest possible tests, based on thefoundations of photoionization theory, to investigate the implications for thegeometry of the emission-line region. The SEDs become more far-ultravioletbright as the Eddington ratio increases, so the equivalent widths ofrecombination lines should also become larger, an effect which we quantify. Theobserved lack of correlation between Eddington ratio and equivalent width showsthat the cloud covering factor must decrease as Eddington ratio increases. Thiswould be consistent with recent models proposing that the broad-line region isa failed dusty wind off the accretion disc.

State-of-the-art AGN SEDs for Photoionization Models: BLR Predictions Confront the Observations