A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING

Huan Yang, Junxian Wang, Zhen Ya Zheng, Sangeeta Malhotra, James E. Rhoads, Leopoldo Infante

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Using the Lyα emission line as a tracer of high-redshift, star-forming galaxies, hundreds of Lyα emission line galaxies (LAEs) at z > 5 have been detected. These LAEs are considered to be low-mass young galaxies, critical to the re-ionization of the universe and the metal enrichment of the circumgalactic medium (CGM) and the intergalactic medium (IGM). It is assumed that outflows in LAEs can help both ionizing photons and Lyα photons escape from galaxies. However, we still know little about the outflows in high-redshift LAEs due to observational difficulties, especially at redshift >5. Models of Lyα radiative transfer predict asymmetric Lyα line profiles with broad red wings in LAEs with outflows. Here, we report a z ∼ 5.7 Lyα emission line with a broad red wing extending to >1000 km s-1 relative to the peak of Lyα line, which has been detected in only a couple of z > 5 LAEs until now. If the broad red wing is ascribed to gas outflow instead of active galactic nucleus activity, the outflow velocity could be larger than the escape velocity (∼500 km s-1) of a typical halo mass of z ∼ 5.7 LAEs, which is consistent with the idea that outflows in LAEs disperse metals to CGM and IGM.

Original languageEnglish (US)
Article number35
JournalAstrophysical Journal
Volume784
Issue number1
DOIs
StatePublished - Mar 20 2014

Fingerprint

outflow
galaxies
wings
intergalactic media
metal
radiative transfer
ionization
tracer
escape velocity
photons
active galactic nuclei
metals
escape
gas
tracers
halos
universe
stars
profiles
gases

Keywords

  • galaxies: evolution
  • galaxies: formation
  • galaxies: high-redshift
  • intergalactic medium

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Yang, H., Wang, J., Zheng, Z. Y., Malhotra, S., Rhoads, J. E., & Infante, L. (2014). A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING. Astrophysical Journal, 784(1), [35]. https://doi.org/10.1088/0004-637X/784/1/35

A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING. / Yang, Huan; Wang, Junxian; Zheng, Zhen Ya; Malhotra, Sangeeta; Rhoads, James E.; Infante, Leopoldo.

In: Astrophysical Journal, Vol. 784, No. 1, 35, 20.03.2014.

Research output: Contribution to journalArticle

Yang, H, Wang, J, Zheng, ZY, Malhotra, S, Rhoads, JE & Infante, L 2014, 'A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING', Astrophysical Journal, vol. 784, no. 1, 35. https://doi.org/10.1088/0004-637X/784/1/35
Yang H, Wang J, Zheng ZY, Malhotra S, Rhoads JE, Infante L. A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING. Astrophysical Journal. 2014 Mar 20;784(1). 35. https://doi.org/10.1088/0004-637X/784/1/35
Yang, Huan ; Wang, Junxian ; Zheng, Zhen Ya ; Malhotra, Sangeeta ; Rhoads, James E. ; Infante, Leopoldo. / A z ∼ 5.7 Lyα EMISSION LINE with AN ULTRABROAD RED WING. In: Astrophysical Journal. 2014 ; Vol. 784, No. 1.
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