气候变化领域集成服务门户(CCPortal): A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S ii]-deficiency

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DOI	10.3847/1538-4357/ab418f
	A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S ii]-deficiency
	Wang B.; Heckman T.M.; Leitherer C.; Alexandroff R.; Borthakur S.; Overzier R.A.
发表日期	2019
ISSN	0004637X
卷号	885 期号:1
英文摘要	The source responsible for the reionization of the universe is believed to be the population of star-forming galaxies at z ∼ 6 to 12. The biggest uncertainty concerns the fraction of Lyman-continuum photons that actually escape from the galaxies. In recent years, several relatively small samples of "leaky" galaxies have been discovered, and clues have begun to emerge as to both the indirect signposts of leakiness and of the conditions/processes that enable the escape of ionizing radiation. In this paper we present the results of a pilot program to test a new technique for finding leaky galaxies, using the weakness of the [S ii] nebular emission lines relative to typical star-forming galaxies as evidence that the interstellar medium (ISM) is optically thin to the Lyman continuum. We use the Cosmic Origins Spectrograph on the Hubble Space Telescope to detect significant emerging flux below the Lyman edge in two out of three [S ii]-weak star-forming galaxies at z ∼ 0.3. We show that these galaxies differ markedly in their properties from the class of leaky "Green-Pea" galaxies at similar redshifts: our sample galaxies are more massive, more metal-rich, and less extreme in terms of their stellar population and the ionization state of the ISM. Like the Green Peas, they have exceptionally high star formation rates per unit area. They also share some properties with the known leaky galaxies at z ∼ 3, but are significantly dustier. Our results validate a new method to identify local laboratories for exploring the processes that made it possible for galaxies to reionize the universe.. The American Astronomical Society. All rights reserved..
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/176312
作者单位	Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, United States; Space Telescope Science Institute, Baltimore, MD 21218, United States; Dunlap Institute for Astronomy and Astrophysics, University of Toronto, Toronto, ON M5S 3H4, Canada; School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, United States; Observatorio Nacional, Rio de Janeiro, Brazil; Institute of Astronomy Geophysics and Atmospheric Sciences, Department of Astronomy, University of São Paulo, São Paulo, SP, 05508-090, Brazil
推荐引用方式 GB/T 7714	Wang B.,Heckman T.M.,Leitherer C.,et al. A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S ii]-deficiency[J],2019,885(1).
APA	Wang B.,Heckman T.M.,Leitherer C.,Alexandroff R.,Borthakur S.,&Overzier R.A..(2019).A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S ii]-deficiency.Astrophysical Journal,885(1).
MLA	Wang B.,et al."A New Technique for Finding Galaxies Leaking Lyman-continuum Radiation: [S ii]-deficiency".Astrophysical Journal 885.1(2019).