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Title: The rest-frame ultraviolet structure of 0.5 < z < 1.5 galaxies

We present the rest-frame UV wavelength dependence of the Petrosian-like half-light radius (r{sub 50}), and the concentration parameter for a sample of 198 star-forming galaxies at 0.5 < z < 1.5. We find a ∼5% decrease in r{sub 50} from 1500 Å to 3000 Å, with half-light radii at 3000 Å ranging from 0.6 kpc to 6 kpc. We also find a decrease in concentration of ∼0.07 (1.9 < C{sub 3000} < 3.9). The lack of a strong relationship between r{sub 50} and wavelength is consistent with a model in which clumpy star formation is distributed over length scales comparable to the galaxy's rest-frame optical light. While the wavelength dependence of r{sub 50} is independent of size at all redshifts, concentration decreases more sharply in the far-UV (∼1500 Å) for large galaxies at z ∼ 1. This decrease in concentration is caused by a flattening of the inner ∼20% of the light profile in disk-like galaxies, indicating that the central regions have different UV colors than the rest of the galaxy. We interpret this as a bulge component with older stellar populations and/or more dust. The size-dependent decrease in concentration is less dramatic at z ∼ 2, suggesting that bulgesmore » are less dusty, younger, and/or less massive than the rest of the galaxy at higher redshifts.« less
Authors:
;  [1] ;  [2] ; ;  [3] ; ; ;  [4] ;  [5] ;  [6] ;  [7]
  1. Cosmology Laboratory (Code 665), NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  2. Physics Department, The Catholic University of America, Washington, DC 20064 (United States)
  3. IPAC, California Institute of Technology, Pasadena, CA 91125 (United States)
  4. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
  5. Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854 (United States)
  6. Inter-University Centre for Astronomy and Astrophysics, Pune (India)
  7. Minnesota Institute for Astrophysics, School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)
Publication Date:
OSTI Identifier:
22365410
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 791; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COLOR; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; COSMOLOGY; DUSTS; ELEMENT ABUNDANCE; FREQUENCY DEPENDENCE; GALAXIES; RED SHIFT; STARS; ULTRAVIOLET RADIATION; VISIBLE RADIATION