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

作者：Damjanov Ivana^*; Chilingarian Igor; Hwang Ho Seong; Geller Margaret J

来源：Astrophysical Journal Letters, 2013, 775(2): L48.

DOI：10.1088/2041-8205/775/2/L48

• galaxies: evolution
• galaxies: fundamental parameters
• galaxies: stellar content
• galaxies: structure

We identify nine galaxies with dynamical masses of M-dyn greater than or similar to 10(10) M-circle dot 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-e,R-c < 6.6 kpc with the median R-e,R-c = 0.74 kpc) for their velocity dispersion (110 < sigma < 340 km s(-1); median sigma = 178 km s(-1)). From the SDSS spectra, three systems are dominated by very young stars; the other six are older than similar to 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-Sersic function. All nine lie below the z similar to 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.

• 出版日期2013-10-1