The Lyman Alpha Reference Sample. II. Hubble Space Telescope Imaging Results, Integrated Properties, and Trends - Archive ouverte HAL Access content directly
Journal Articles The Astrophysical Journal Year : 2014

The Lyman Alpha Reference Sample. II. Hubble Space Telescope Imaging Results, Integrated Properties, and Trends

, , , , , , , (1) , , , , , , (2) , , , , ,
1
2
Matthew Hayes
Göran Östlin
  • Function : Author
Florent Duval
  • Function : Author
Andreas Sandberg
  • Function : Author
Lucia Guaita
  • Function : Author
Jens Melinder
  • Function : Author
Angela Adamo
  • Function : Author
Anne Verhamme
  • Function : Author
Ivana Orlitová
  • Function : Author
J. Miguel Mas-Hesse
  • Function : Author
John M. Cannon
  • Function : Author
Hakim Atek
Peter Laursen
  • Function : Author
Héctor Otí-Floranes
  • Function : Author
Stephen Pardy
  • Function : Author
Thøger Rivera-Thorsen
  • Function : Author
E. Christian Herenz
  • Function : Author

Abstract

We report new results regarding the Lyα output of galaxies, derived from the Lyman Alpha Reference Sample, and focused on Hubble Space Telescope imaging. For 14 galaxies we present intensity images in Lyα, Hα, and UV, and maps of Hα/Hβ, Lyα equivalent width (EW), and Lyα/Hα. We present Lyα and UV radial light profiles and show they are well-fitted by Sérsic profiles, but Lyα profiles show indices systematically lower than those of the UV (n ≈ 1-2 instead of >~ 4). This reveals a general lack of the central concentration in Lyα that is ubiquitous in the UV. Photometric growth curves increase more slowly for Lyα than the far ultraviolet, showing that small apertures may underestimate the EW. For most galaxies, however, flux and EW curves flatten by radii ≈10 kpc, suggesting that if placed at high-z only a few of our galaxies would suffer from large flux losses. We compute global properties of the sample in large apertures, and show total Lyα luminosities to be independent of all other quantities. Normalized Lyα throughput, however, shows significant correlations: escape is found to be higher in galaxies of lower star formation rate, dust content, mass, and nebular quantities that suggest harder ionizing continuum and lower metallicity. Six galaxies would be selected as high-z Lyα emitters, based upon their luminosity and EW. We discuss the results in the context of high-z Lyα and UV samples. A few galaxies have EWs above 50 Å, and one shows f_{esc}^{{Ly}\alpha } of 80%; such objects have not previously been reported at low-z.

Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program No.12310.

Dates and versions

insu-03645714 , version 1 (19-04-2022)

Identifiers

Cite

Matthew Hayes, Göran Östlin, Florent Duval, Andreas Sandberg, Lucia Guaita, et al.. The Lyman Alpha Reference Sample. II. Hubble Space Telescope Imaging Results, Integrated Properties, and Trends. The Astrophysical Journal, 2014, 782, ⟨10.1088/0004-637X/782/1/6⟩. ⟨insu-03645714⟩
6 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More