CANDELS OBSERVATIONS OF THE STRUCTURAL PROPERTIES OF CLUSTER GALAXIES AT z = 1.62

Journal Article · Thu May 10 04:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/750/2/93· OSTI ID:22034539

Papovich, C; Bassett, R; Tran, K -V; Finkelstein, S L; Finkelstein, K D ^[1]; Lotz, J M; Ferguson, H C; Koekemoer, A M ^[2]; Van der Wel, A ^[3]; Bell, E F ^[4]; Conselice, C J; Haeussler, B ^[5]; Dekel, A ^[6]; Dunlop, J S ^[7]; Guo, Yicheng ^[8]; Faber, S M; Kocevski, D D; Koo, D C; McGrath, E J ^[9]; Farrah, D ^[10] ; others, and

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1. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843-4242 (United States)
2. Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)
3. Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, D-69117, Heidelberg (Germany)
4. Department of Astronomy, University of Michigan, Ann Arbor, MI 48109 (United States)
5. School of Physics and Astronomy, University of Nottingham, Nottingham (United Kingdom)
6. Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)
7. Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh (United Kingdom)
8. Astronomy Department, University of Massachusetts, Amherst, MA 01003 (United States)
9. UCO/Lick Observatory, Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)
10. Astronomy Centre, University of Sussex, Falmer, Brighton (United Kingdom)

We discuss the structural and morphological properties of galaxies in a z = 1.62 proto-cluster using near-IR imaging data from Hubble Space Telescope Wide Field Camera 3 data of the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS). The cluster galaxies exhibit a clear color-morphology relation: galaxies with colors of quiescent stellar populations generally have morphologies consistent with spheroids, and galaxies with colors consistent with ongoing star formation have disk-like and irregular morphologies. The size distribution of the quiescent cluster galaxies shows a deficit of compact ({approx}< 1 kpc), massive galaxies compared to CANDELS field galaxies at z = 1.6. As a result, the cluster quiescent galaxies have larger average effective sizes compared to field galaxies at fixed mass at greater than 90% significance. Combined with data from the literature, the size evolution of quiescent cluster galaxies is relatively slow from z {approx_equal} 1.6 to the present, growing as (1 + z){sup -0.6{+-}0.1}. If this result is generalizable, then it implies that physical processes associated with the denser cluster region seem to have caused accelerated size growth in quiescent galaxies prior to z = 1.6 and slower subsequent growth at z < 1.6 compared to galaxies in the lower density field. The quiescent cluster galaxies at z = 1.6 have higher ellipticities compared to lower redshift samples at fixed mass, and their surface-brightness profiles suggest that they contain extended stellar disks. We argue that the cluster galaxies require dissipationless (i.e., gas-poor or 'dry') mergers to reorganize the disk material and to match the relations for ellipticity, stellar mass, size, and color of early-type galaxies in z < 1 clusters.

• OSTI ID: 22034539
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 750; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTRONOMY
ASTROPHYSICS
BRIGHTNESS
CAMERAS
COLOR
DENSITY
DISTRIBUTION
GALACTIC EVOLUTION
GALAXIES
GALAXY CLUSTERS
INFRARED RADIATION
MASS
MORPHOLOGY
RED SHIFT
STARS