The DOI matches its Crossref record; 49 of the 49 references it cites were found in a registry or an index.
The diversity of quasars unified by accretion and orientation
Open accessAbstract
Quasars are rapidly accreting supermassive black holes at the centres of massive galaxies. They display a broad range of properties across all wavelengths, reflecting the diversity in the physical conditions of the regions close to the central engine. These properties, however, are not random, but form well-defined trends. The dominant trend is known as ‘Eigenvector 1’, in which many properties correlate with the strength of optical iron and [O iii] emission. The main physical driver of Eigenvector 1 has long been suspected to be the quasar luminosity normalized by the mass of the hole (the ‘Eddington ratio’), which is an important parameter of the black hole accretion process. But a definitive proof has been missing. Here we report an analysis of archival data that reveals that the Eddington ratio indeed drives Eigenvector 1. We also find that orientation plays a significant role in determining the observed kinematics of the gas in the broad-line region, implying a flattened, disk-like geometry for the fast-moving clouds close to the black hole. Our results show that most of the diversity of quasar phenomenology can be unified using two simple quantities: Eddington ratio and orientation.
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Cites
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Unified Schemes for Radio-Loud Active Galactic Nuclei
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Coevolution (Or Not) of Supermassive Black Holes and Host Galaxies
Kormendy, J., & Ho, L. C. (2013) · Annual Review of Astronomy and Astrophysics · doi:10.1146/annurev-astro-082708-101811 · Cited by 4,196
Self-citationUnified Models for Active Galactic Nuclei and Quasars
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Eisenstein, D. J., Weinberg, D. H., Agol, E., Aihara, H., Allende Prieto, C., Anderson, S. F., Arns, J. A., Aubourg, É., Bailey, S., Balbinot, E., et al. (2011) · The Astronomical Journal · doi:10.1088/0004-6256/142/3/72 · Cited by 2,179
Coevolution (Or Not) of Supermassive Black Holes and Host GalaxiesPreprint
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Self-citationPeterson, B. M., Ferrarese, L., Gilbert, K. M., Kaspi, S., Malkan, M. A., Maoz, D., Merritt, D., Netzer, H., Onken, C. A., Pogge, R. W., et al. (2004) · The Astrophysical Journal · doi:10.1086/423269 · Cited by 1,802
The emission-line properties of low-redshift quasi-stellar objects
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A CATALOG OF QUASAR PROPERTIES FROM SLOAN DIGITAL SKY SURVEY DATA RELEASE 7
Shen, Y., Richards, G. T., Strauss, M. A., Hall, P. B., Schneider, D. P., Snedden, S., Bizyaev, D., Brewington, H., Malanushenko, V., Malanushenko, E., et al. (2011) · The Astrophysical Journal Supplement Series · doi:10.1088/0067-0049/194/2/45 · Cited by 1,517
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Cited by
THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: TECHNICAL OVERVIEW
Shen, Y., Brandt, W. N., Dawson, K. S., Hall, P. B., McGreer, I. D., Anderson, S. F., Chen, Y., Denney, K. D., Eftekharzadeh, S., Fan, X., et al. (2014) · The Astrophysical Journal Supplement Series · doi:10.1088/0067-0049/216/1/4 · Cited by 210
Self-citationGiustini, M., & Proga, D. (2019) · Astronomy & Astrophysics · doi:10.1051/0004-6361/201833810 · Cited by 166
“The Eddington ratio ṁ is likely the main physical driver of physical differences in the accretion flow that lead to different observed phenomenology of AGN (e.g., the Eigenvector 1: Sulentic et al. 2000b; Marziani et al. 2001; Boroson 2002; Shen & Ho 2014).”
BackgroundWhat drives the growth of black holes: A decade of progress
Alexander, D. M., Hickox, R. C., Aird, J., Combes, F., Costa, T., Habouzit, M., Harrison, C. M., Leng, R. I., Morabito, L. K., Uckelman, S. L., et al. (2025) · New Astronomy Reviews · doi:10.1016/j.newar.2025.101733 · Cited by 18
Metadata
- Authors
- Shen, Y., & Ho, L. C.
- Venue
- Nature
- Published
- 2014-09-10
- Volume
- 513
- Issue
- 7517
- Pages
- 210-213
- ISSN
- 0028-0836 (ISSN-L)
- 1476-4687
- OpenAlex
- W2093290764
- Cited by
- 373
- References
- 49
- FWCI
- 16.55
- Type
- journal article
- Language
- en
- Open access
- green
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