Broad-line region in active galactic nuclei: Dusty or dustless?

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F23%3A00134415" target="_blank" >RIV/00216224:14310/23:00134415 - isvavai.cz</a>

Result on the web

<a href="https://www.aanda.org/articles/aa/full_html/2023/12/aa47819-23/aa47819-23.html" target="_blank" >https://www.aanda.org/articles/aa/full_html/2023/12/aa47819-23/aa47819-23.html</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202347819" target="_blank" >10.1051/0004-6361/202347819</a>

Result language

angličtina

Original language name

Broad-line region in active galactic nuclei: Dusty or dustless?

Original language description

Context. Dust in active galactic nuclei is clearly present right outside the broad-line region (BLR) in the form of a dusty molecular torus. However, some models of the BLR predict that dust may also exist within the BLR. Aims. We study the reprocessing of radiation by the BLR with the aim of observing how the presence of dust affects the reprocessed continuum and the line properties. Methods.We calculated a range of models using the CLOUDY photoionisation code for dusty and dustless plasma. We paid particular attention to the well-studied object NGC 5548, and we compared the line equivalent width predictions with the data from observations for this object. Results. We obtained a rough agreement between the expected equivalent widths of the Hβ and Mg II lines and the observed values for NGC 5548 for the line distances implied by the time-delay measurement (for Hβ) and the radius-luminosity relation (for Mg II) when the medium is dusty. We found the incident radiation to be consistent with the radiation seen by the observer, so no shielding between the inner disc and the BLR is required. High ionisation lines such as He II, however, clearly form in the inner dustless region. When the additional absorber is present, the Hβ emitting region moves closer to the dustless part of the accretion disc surface.

Czech name

—

Czech description

—

Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

<a href="/en/project/GX21-13491X" target="_blank" >GX21-13491X: Exploring the Hot Universe and Understanding Cosmic Feedback</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy and Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Volume of the periodical

680

Issue of the periodical within the volume

December 2023

Country of publishing house

FR - FRANCE

Number of pages

10

Pages from-to

1-10

UT code for WoS article

001125494400022

EID of the result in the Scopus database

2-s2.0-85180811711