Pith. sign in

REVIEW 7 cited by

Broad iron lines in Active Galactic Nuclei

Not yet reviewed by Pith; the record is open.

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv astro-ph/0004366 v1 pith:LUB335J5 submitted 2000-04-26 astro-ph

Broad iron lines in Active Galactic Nuclei

classification astro-ph
keywords lineironaccretionblackbroadactivearounddisk
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
0 comments
read the original abstract

An intrinsically narrow line emitted by an accretion disk around a black hole appears broadened and skewed as a result of the Doppler effect and gravitational redshift. The fluorescent iron line in the X-ray band at 6.4-6.9keV is the strongest such line and is seen in the X-ray spectrum of many active galactic nuclei and, in particular, Seyfert galaxies. It is an important diagnostic with which to study the geometry and other properties of the accretion flow very close to the central black hole. The broad iron line indicates the presence of a standard thin accretion disk in those objects, often seen at low inclination. The broad iron line has opened up strong gravitational effects around black holes to observational study with wide-reaching consequences for both astrophysics and physics.

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 7 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. The emergence of X-ray emission lines during relativistic radio-jet formation in the changing-look active galactic nucleus 1ES 1927+654

    astro-ph.HE 2026-07 conditional novelty 6.0

    X-ray emission lines and a broad iron feature emerged in changing-look AGN 1ES 1927+654 concurrently with radio-jet formation and declining ionized outflows from 2022 to 2025.

  2. Physically motivated AGN emissivity profiles and their effects on quasar microlensing signatures. 1. Multi-epoch accretion disc size inference

    astro-ph.GA 2026-07 accept novelty 6.0

    Interpreting composite disc-plus-BLR emission as a single compact disc systematically overestimates microlensing half-light radii, with the bias set mainly by the BLR flux fraction and the compact-disc emissivity shape.

  3. HALO II: Constraining Hubble constant $H_{0}$ through continuum delay fitting of Fairall 9

    astro-ph.GA 2026-06 unverdicted novelty 6.0

    Using simultaneous modeling of continuum lag-spectrum and broadband SED of Fairall 9 with the H0RIZON-AGN model, the authors obtain H0 = 72.4_{-3.7}^{+3.4} km s^{-1} Mpc^{-1}.

  4. Simulation-Based Prediction of Black Hole Fe K$\alpha$ Line Profiles

    astro-ph.HE 2026-05 conditional novelty 6.0

    Fe Kα lines from accreting black holes are produced mostly outside 10 gravitational radii due to radial ionization gradients, allowing broad profiles without high spin.

  5. Tidal perturbations of an extreme mass ratio inspiral around a Kerr black hole

    gr-qc 2026-01 conditional novelty 6.0

    A closed-form Kerr metric under slow quadrupolar tides yields spin-dependent tidal shifts of the ISCO and light ring, with larger shifts for retrograde orbits around fast-spinning holes.

  6. Unification models of Active Galactic Nuclei

    astro-ph.GA 2026-06 conditional novelty 2.0

    A review of AGN unification concluding that whether a black-hole-powered nucleus appears obscured depends on inclination, Eddington ratio (radiative feedback), and host-galaxy merger/redshift evolution.

  7. Unification models of Active Galactic Nuclei

    astro-ph.GA 2026-06 unverdicted

    Overview chapter summarizing traditional orientation-based and radiation-regulated unification models for AGN, including evolutionary aspects and changing-look AGN.