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

J 2023

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

PANDEY, Ashwani, Bozena CZERNY, Swayamtrupta PANDA, Raj PRINCE, Vikram Kumar JAISWAL et. al.

Basic information

Original name

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

Authors

PANDEY, Ashwani, Bozena CZERNY, Swayamtrupta PANDA, Raj PRINCE, Vikram Kumar JAISWAL, Mary Loli MARTINEZ-ALDAMA, Michal ZAJAČEK (703 Slovakia, belonging to the institution) and Marzena SNIEGOWSKA

Edition

Astronomy and Astrophysics, EDP Sciences, 2023, 0004-6361

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

France

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

URL

Impact factor

Impact factor: 6.500 in 2022

RIV identification code

RIV/00216224:14310/23:00134415

Organization unit

Faculty of Science

DOI

http://dx.doi.org/10.1051/0004-6361/202347819

UT WoS

001125494400022

Keywords in English

galaxies: active; galaxies: Seyfert; methods: numerical

Abstract

V originále

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.

Links

GX21-13491X, research and development project

Name: Zkoumání žhavého vesmíru a porozumění kosmické zpětné vazbě (Acronym: EHU)

Investor: Czech Science Foundation

Citovat

PANDEY, Ashwani, Bozena CZERNY, Swayamtrupta PANDA, Raj PRINCE, Vikram Kumar JAISWAL, Mary Loli MARTINEZ-ALDAMA, Michal ZAJAČEK and Marzena SNIEGOWSKA. Broad-line region in active galactic nuclei: Dusty or dustless? Astronomy and Astrophysics. EDP Sciences, 2023, vol. 680, December 2023, p. 1-10. ISSN 0004-6361. Available from: https://dx.doi.org/10.1051/0004-6361/202347819.

@article{2377103,
   author = {Pandey, Ashwani and Czerny, Bozena and Panda, Swayamtrupta and Prince, Raj and Jaiswal, Vikram Kumar and MartinezandAldama, Mary Loli and Zajaček, Michal and Sniegowska, Marzena},
   article_number = {December 2023},
   doi = {http://dx.doi.org/10.1051/0004-6361/202347819},
   keywords = {galaxies: active; galaxies: Seyfert; methods: numerical},
   language = {eng},
   issn = {0004-6361},
   journal = {Astronomy and Astrophysics},
   title = {Broad-line region in active galactic nuclei: Dusty or dustless?},
   url = {https://www.aanda.org/articles/aa/full_html/2023/12/aa47819-23/aa47819-23.html},
   volume = {680},
   year = {2023}
}

TY  - JOUR
ID  - 2377103
AU  - Pandey, Ashwani - Czerny, Bozena - Panda, Swayamtrupta - Prince, Raj - Jaiswal, Vikram Kumar - Martinez-Aldama, Mary Loli - Zajaček, Michal - Sniegowska, Marzena
PY  - 2023
TI  - Broad-line region in active galactic nuclei: Dusty or dustless?
JF  - Astronomy and Astrophysics
VL  - 680
IS  - December 2023
SP  - 1-10
EP  - 1-10
PB  - EDP Sciences
SN  - 00046361
KW  - galaxies: active
KW  - galaxies: Seyfert
KW  - methods: numerical
UR  - https://www.aanda.org/articles/aa/full_html/2023/12/aa47819-23/aa47819-23.html
N2  - 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.
ER  -

PANDEY, Ashwani, Bozena CZERNY, Swayamtrupta PANDA, Raj PRINCE, Vikram Kumar JAISWAL, Mary Loli MARTINEZ-ALDAMA, Michal ZAJAČEK and Marzena SNIEGOWSKA. Broad-line region in active galactic nuclei: Dusty or dustless? \textit{Astronomy and Astrophysics}. EDP Sciences, 2023, vol.~680, December 2023, p.~1-10. ISSN~0004-6361. Available from: https://dx.doi.org/10.1051/0004-6361/202347819.

Detailed Information on Publication Record