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Title: DISCOVERY OF NINE INTERMEDIATE-REDSHIFT COMPACT QUIESCENT GALAXIES IN THE SLOAN DIGITAL SKY SURVEY

We identify nine galaxies with dynamical masses of M {sub dyn} ∼> 10{sup 10} M {sub ☉} as photometric point sources, but with redshifts between z = 0.2 and z = 0.6, in the Sloan Digital Sky Survey (SDSS) spectro-photometric database. All nine galaxies have archival Hubble Space Telescope images. Surface brightness profile fitting confirms that all nine galaxies are extremely compact (0.4 < R {sub e,c} < 6.6 kpc with the median R {sub e,c} = 0.74 kpc) for their velocity dispersion (110 < σ < 340 km s{sup –1}; median σ = 178 km s{sup –1}). From the SDSS spectra, three systems are dominated by very young stars; the other six are older than ∼1 Gyr (two are E+A galaxies). The three young galaxies have disturbed morphologies and the older systems have smooth profiles consistent with a single-Sérsic function. All nine lie below the z ∼ 0 velocity dispersion-half-light radius relation. The most massive system—SDSSJ123657.44+631115.4—lies right within the locus for massive compact z > 1 galaxies and the other eight objects follow the high-redshift dynamical size-mass relation.
Authors:
 [1] ; ; ;  [2]
  1. Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)
  2. Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22215457
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 775; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BRIGHTNESS; DISPERSIONS; EVOLUTION; FUNCTIONS; GALAXIES; IMAGES; MASS; MORPHOLOGY; POINT SOURCES; RED SHIFT; SKY; SPACE; SPECTRA; STARS; TELESCOPES; VELOCITY