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Title: CANDELS: THE CORRELATION BETWEEN GALAXY MORPHOLOGY AND STAR FORMATION ACTIVITY AT z {approx} 2

We discuss the state of the assembly of the Hubble sequence in the mix of bright galaxies at redshift 1.4 < z {<=} 2.5 with a large sample of 1671 galaxies down to H{sub AB} {approx} 26, selected from the HST/ACS and WFC3 images of the GOODS-South field obtained as part of the GOODS and CANDELS observations. We investigate the relationship between the star formation properties and morphology using various parametric diagnostics, such as the Sersic light profile, Gini (G), M{sub 20}, concentration (C), asymmetry (A), and multiplicity ({Psi}) parameters. Our sample clearly separates into massive, red, and passive galaxies versus less massive, blue, and star-forming ones, and this dichotomy correlates very well with the galaxies' morphological properties. Star-forming galaxies show a broad variety of morphological features, including clumpy structures and bulges mixed with faint low surface brightness features, generally characterized by disky-type light profiles. Passively evolving galaxies, on the other hand, very often have compact light distribution and morphology typical of today's spheroidal systems. We also find that artificially redshifted local galaxies have a similar distribution with z {approx} 2 galaxies in a G-M{sub 20} plane. Visual inspection between the rest-frame optical and UV images show that there ismore » a generally weak morphological k-correction for galaxies at z {approx} 2, but the comparison with non-parametric measures show that galaxies in the rest-frame UV are somewhat clumpier than rest-frame optical. Similar general trends are observed in the local universe among massive galaxies, suggesting that the backbone of the Hubble sequence was already in place at z {approx} 2.« less
Authors:
; ;  [1] ; ;  [2] ; ; ; ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10]
  1. Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)
  2. University of California Observatories/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States)
  3. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
  4. Max-Planck Institut fuer Astronomie, Koenigstuhl 17, D-69117 Heidelberg (Germany)
  5. Department of Physics and Astronomy, University of Kentucky, Lexington, KY 40506 (United States)
  6. University of Nottingham, School of Physics and Astronomy, Nottingham NG7 2Rd (United Kingdom)
  7. Max-Planck Institut fuer Extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany)
  8. Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)
  9. NOAO-Tuscon, 950 North Cherry Avenue, Tucson, AZ 85719 (United States)
  10. Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI 48109 (United States)
Publication Date:
OSTI Identifier:
22133957
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 774; 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; BRIGHTNESS; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; IMAGES; MILKY WAY; MORPHOLOGY; MULTIPLICITY; RED SHIFT; STARS; UNIVERSE; VISIBLE RADIATION