气候变化领域集成服务门户(CCPortal): Direct T e Metallicity Calibration of R23 in Strong Line Emitters

CCPortal

DOI	10.3847/1538-4357/aaee8a
	Direct T e Metallicity Calibration of R23 in Strong Line Emitters
	Jiang T.; Malhotra S.; Rhoads J.E.; Yang H.
发表日期	2019
ISSN	0004637X
卷号	872 期号:2
英文摘要	The gas metallicity of galaxies is often estimated using strong emission lines such as the optical lines of [O iii] and [O ii]. The most common measure is "R23," defined as ([O ii]λλ3726, 3729 + [O iii]λλ4959,5007)/Hβ. Most calibrations for these strong-line metallicity indicators are for continuum selected galaxies. We report a new empirical calibration of R23 for extreme emission-line galaxies using a large sample of about 800 star-forming green pea galaxies with reliable T e -based gas-phase metallicity measurements. This sample is assembled from Sloan Digital Sky Survey (SDSS) Data Release 13 with the equivalent width of the line [O iii]λ5007 > 300A or the equivalent width of the line Hβ > 100 A in the redshift range 0.011 < z < 0.411. For galaxies with strong emission lines and large ionization parameter (which manifests as log [O iii]λλ4959,5007/[O ii]λλ3726,3729 ≥0.6), R23 monotonically increases with log(O/H) and the double-value degeneracy is broken. Our calibration provides metallicity estimates that are accurate to within ∼0.14 dex in this regime. Many previous R23 calibrations are found to have bias and large scatter for extreme emission-line galaxies. We give formulae and plots to directly convert R23 and [O iii]λλ4959,5007/[O ii]λλ3726,3729 to log(O/H). Since green peas are best nearby analogs of high-redshift Lyα emitting galaxies, the new calibration offers a good way to estimate the metallicities of both extreme emission-line galaxies and high-redshift Lyα emitting galaxies. We also report on 15 galaxies with metallicities less than 1/12 solar, with the lowest metallicities being 12+log(O/H) = 7.25 and 7.26.. The American Astronomical Society. All rights reserved..
英文关键词	galaxies: abundances; galaxies: evolution; galaxies: starburst; ISM: abundances
来源期刊	Astrophysical Journal
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/176550
作者单位	School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, United States; Department of Astronomy, University of Maryland, College Park, MD 20742, United States; NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States; Las Campanas Observatory, Carnegie Observatories, La Serena, Chile
推荐引用方式 GB/T 7714	Jiang T.,Malhotra S.,Rhoads J.E.,et al. Direct T e Metallicity Calibration of R23 in Strong Line Emitters[J],2019,872(2).
APA	Jiang T.,Malhotra S.,Rhoads J.E.,&Yang H..(2019).Direct T e Metallicity Calibration of R23 in Strong Line Emitters.Astrophysical Journal,872(2).
MLA	Jiang T.,et al."Direct T e Metallicity Calibration of R23 in Strong Line Emitters".Astrophysical Journal 872.2(2019).