Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei
The distinct behaviors of blue- and redshifted broad emission-line shifts, emitted by ionic species with varying ionization potentials in active galactic nuclei (AGN), can be elucidated by considering the balance between radiation and gravitational forces along the quasar main sequence. Blueshifts a...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-10-01
|
| Series: | Symmetry |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2073-8994/15/10/1859 |
| _version_ | 1797572181000978432 |
|---|---|
| author | Paola Marziani |
| author_facet | Paola Marziani |
| author_sort | Paola Marziani |
| collection | DOAJ |
| description | The distinct behaviors of blue- and redshifted broad emission-line shifts, emitted by ionic species with varying ionization potentials in active galactic nuclei (AGN), can be elucidated by considering the balance between radiation and gravitational forces along the quasar main sequence. Blueshifts are attributed to outflowing motions of the line-emitting gas toward the observer, and they are most pronounced in AGN with high Eddington ratios (Population A) and high luminosities. Conversely, redshifts in the broad-line wings are observed in Balmer emission lines of sources radiating at low Eddington ratios (Population B), though the origin of these redshifts remains a subject of ongoing debate. A correlation linking the redward asymmetry as measured by the centroid shift of the <span style="font-variant: small-caps;">H</span><inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>β</mi></semantics></math></inline-formula> line profile to the black hole mass lends support to the notion that these shifts arise from gravitational and transverse redshift effects, particularly for black hole masses <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>M</mi><mi>BH</mi></msub><mo>≳</mo><msup><mn>10</mn><mrow><mn>8.7</mn></mrow></msup></mrow></semantics></math></inline-formula> M<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mo>⊙</mo></msub></semantics></math></inline-formula>. |
| first_indexed | 2024-03-10T20:51:42Z |
| format | Article |
| id | doaj.art-4ac9019a0e84450aaf52bc87bc00402b |
| institution | Directory Open Access Journal |
| issn | 2073-8994 |
| language | English |
| last_indexed | 2024-03-10T20:51:42Z |
| publishDate | 2023-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Symmetry |
| spelling | doaj.art-4ac9019a0e84450aaf52bc87bc00402b2023-11-19T18:17:48ZengMDPI AGSymmetry2073-89942023-10-011510185910.3390/sym15101859Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic NucleiPaola Marziani0National Institute for Astrophysics (INAF), Astronomical Observatory of Padova, 35122 Padova, ItalyThe distinct behaviors of blue- and redshifted broad emission-line shifts, emitted by ionic species with varying ionization potentials in active galactic nuclei (AGN), can be elucidated by considering the balance between radiation and gravitational forces along the quasar main sequence. Blueshifts are attributed to outflowing motions of the line-emitting gas toward the observer, and they are most pronounced in AGN with high Eddington ratios (Population A) and high luminosities. Conversely, redshifts in the broad-line wings are observed in Balmer emission lines of sources radiating at low Eddington ratios (Population B), though the origin of these redshifts remains a subject of ongoing debate. A correlation linking the redward asymmetry as measured by the centroid shift of the <span style="font-variant: small-caps;">H</span><inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>β</mi></semantics></math></inline-formula> line profile to the black hole mass lends support to the notion that these shifts arise from gravitational and transverse redshift effects, particularly for black hole masses <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>M</mi><mi>BH</mi></msub><mo>≳</mo><msup><mn>10</mn><mrow><mn>8.7</mn></mrow></msup></mrow></semantics></math></inline-formula> M<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mo>⊙</mo></msub></semantics></math></inline-formula>.https://www.mdpi.com/2073-8994/15/10/1859active galactic nucleioptical spectroscopyionized gasbroad-line region |
| spellingShingle | Paola Marziani Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei Symmetry active galactic nuclei optical spectroscopy ionized gas broad-line region |
| title | Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei |
| title_full | Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei |
| title_fullStr | Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei |
| title_full_unstemmed | Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei |
| title_short | Accretion/Ejection Phenomena and Emission-Line Profile (A)symmetries in Type-1 Active Galactic Nuclei |
| title_sort | accretion ejection phenomena and emission line profile a symmetries in type 1 active galactic nuclei |
| topic | active galactic nuclei optical spectroscopy ionized gas broad-line region |
| url | https://www.mdpi.com/2073-8994/15/10/1859 |
| work_keys_str_mv | AT paolamarziani accretionejectionphenomenaandemissionlineprofileasymmetriesintype1activegalacticnuclei |