EVOLUTION IN THE CONTINUUM MORPHOLOGICAL PROPERTIES OF Ly{alpha}-EMITTING GALAXIES FROM z = 3.1 TO z = 2.1

Journal Article · Tue Jul 10 04:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/753/2/95· OSTI ID:22039427

Bond, Nicholas A; Gawiser, Eric ^[1]; Guaita, Lucia ^[2]; Padilla, Nelson ^[3]; Gronwall, Caryl; Ciardullo, Robin ^[4]; Lai, Kamson ^[5]

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1. Physics and Astronomy Department, Rutgers University, Piscataway, NJ 08854-8019 (United States)
2. Department of Astronomy, Stockholm University, AlbaNova Science Center, SE-106 91 Stockholm (Sweden)
3. Departmento de Astronomia y Astrofisica, Pontificia Universidad Catolica de Chile, Santiago (Chile)
4. Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States)
5. University of California Observatoires/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States)

We present a rest-frame ultraviolet morphological analysis of 108 z {approx_equal} 2.1 Ly{alpha} emitters (LAEs) in the Extended Chandra Deep Field South and compare it to a similar sample of 171 LAEs at z {approx_equal} 3.1. Using Hubble Space Telescope images from the Galaxy Evolution from Morphology and SEDs survey, Great Observatories Origins Deep Survey, and Hubble Ultradeep Field, we measure size and photometric component distributions, where photometric components are defined as distinct clumps of UV-continuum emission. At both redshifts, >80% of LAEs have observed half-light radii <2 kpc, but the median half-light radius rises from 0.95 {+-} 0.04 kpc at z 3.1 to 1.41 {+-} 0.14 kpc at z = 2.1. A similar evolution is seen in the sizes of individual rest-UV components, but there is no evidence for evolution in the number of multi-component systems. In the z = 2.1 sample, we see clear correlations between the size of an LAE and other physical properties derived from its spectral energy distribution (SED). LAEs are found to be larger for galaxies with higher stellar mass, star formation rate, and dust obscuration, but there is no evidence for a trend between equivalent width and half-light radius at either redshift. The presence of these correlations suggests that a wide range of objects are being selected by LAE surveys at z {approx} 2, including a significant fraction of objects for which a massive and moderately extended population of old stars underlies the young starburst giving rise to the Ly{alpha} emission.

• OSTI ID: 22039427
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 753; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTRONOMY
ASTROPHYSICS
COMPARATIVE EVALUATIONS
CORRELATIONS
COSMOLOGY
ENERGY SPECTRA
GALACTIC EVOLUTION
GALAXIES
LYMAN LINES
MASS
MORPHOLOGY
PHOTOMETRY
RED SHIFT
STARS
ULTRAVIOLET RADIATION
VISIBLE RADIATION