SIZES OF LYalpha-EMITTING GALAXIES AND THEIR REST-FRAME ULTRAVIOLET COMPONENTS AT z = 3.1

Journal Article · Sun Nov 01 04:00:00 EST 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/705/1/639· OSTI ID:21378353

Bond, Nicholas A; Gawiser, Eric ^[1]; Gronwall, Caryl; Ciardullo, Robin ^[2]; Altmann, Martin ^[3]; Schawinski, Kevin ^[4]

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1. Physics and Astronomy Department, Rutgers University Piscataway, NJ 08854-8019 (United States)
2. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)
3. University of Heidelberg, Center for Astronomy, Moenchhofstr. 12-14, D-69120 Heidelberg (Germany)
4. Department of Physics, Yale University, New Haven, CT 06511 (United States)

We present a rest-frame ultraviolet analysis of approx120 z approx 3.1 Lyman Alpha Emitters (LAEs) in the Extended Chandra Deep Field South. Using Hubble Space Telescope (HST) images taken as part of the Galaxy Evolution From Morphology and SEDS (GEMS) survey, Great Observatories Origins Deep Survey (GOODS), and Hubble Ultradeep Field surveys, we analyze the sizes of LAEs, as well as the spatial distribution of their components, which are defined as distinct clumps of UV-continuum emission. We set an upper limit of approx1 kpc (approx0.''1) on the rms offset between the centroids of the continuum and Lyalpha emission. The SFRs of LAE components inferred from the rest-frame ultraviolet continuum range from approx0.1 M{sub sun} yr{sup -1} to approx5 M{sub sun} yr{sup -1}. A subsample of LAEs with coverage in multiple surveys (at different imaging depths) suggests that one needs a signal-to-noise ratio, S/N approx>30, in order to make a robust estimate of the half-light radius of an LAE system. The majority of LAEs have observed half-light radii approx<2 kpc, and LAE components typically have observed half-light radii approx<1.5 kpc (approx<0.''20). Although only approx50% of the detected LAE components are resolved at GOODS depth, the brightest (V approx< 26.3) are all resolved in both GOODS and GEMS. Since we find little evidence for a correlation between the rest-UV sizes and magnitudes of LAEs, the majority should be resolved in a deeper survey at the approx0.''05 angular resolution of the HST. Most of the multi-component LAEs identified in shallow frames become connected in deeper images, suggesting that the majority of the rest-UV 'clumps' are individual star-forming regions within a single system.

• OSTI ID: 21378353
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 705; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CORRELATIONS
COSMOLOGY
DIMENSIONLESS NUMBERS
DISTRIBUTION
ELECTROMAGNETIC RADIATION
EMISSION
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
RADIATIONS
RED SHIFT
SIGNAL-TO-NOISE RATIO
SPATIAL DISTRIBUTION
STARS
TELESCOPES
ULTRAVIOLET RADIATION
VISIBLE RADIATION