METALLICITY AND QUASAR OUTFLOWS

Journal Article · Fri Jun 01 04:00:00 EDT 2012 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/751/2/L23· OSTI ID:22047799

Wang, Huiyuan; Zhou, Hongyan; Wang, Tinggui ^[1]; Yuan, Weimin ^[2]

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1. Key Laboratory for Research in Galaxies and Cosmology, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, Anhui 230026 (China)
2. National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

Correlations of the outflow strength of quasars, as measured by the blueshift and asymmetry index (BAI) of the C IV line, with intensities and ratios of broad emission lines, based on composite quasar spectra built from the Sloan Digital Sky Survey, are investigated. We find that most of the line ratios of other ions to C IV increase prominently with BAI. These behaviors can be well understood in the context of increasing metallicity with BAI. The strength of the dominant coolant, C IV line, decreases, and weak collisionally excited lines increase with gas metallicity as a result of the competition between different line coolants. Using Si IV+O IV]/C IV as an indicator of gas metallicity, we present, for the first time, a strong correlation between the metallicity and the outflow strength of quasars over a wide range of 1.7-6.9 times solar abundance. Our result implies that metallicity plays an important role in the formation of quasar outflows, likely by affecting outflow acceleration. This effect may have a profound impact on galaxy evolution via momentum feedback and chemical enrichment.

• OSTI ID: 22047799
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 751; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ACCELERATION
ASTRONOMY
ASTROPHYSICS
ASYMMETRY
CARBON IONS
CORRELATIONS
ELEMENT ABUNDANCE
FEEDBACK
GALACTIC EVOLUTION
GALAXIES
GALAXY NUCLEI
INDEXES
METALS
QUASARS
SILICON IONS