Central galaxies in different environments: Do they have similar properties?

Journal Article · Tue Jun 10 04:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/788/1/29· OSTI ID:22356700

Lacerna, I.; Avila-Reese, V.; Hernández-Toledo, H. M. ^[1]; Rodríguez-Puebla, A. ^[2]

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1. Instituto de Astronomía, Universidad Nacional Autónoma de México, A. P. 70-264, 04510 México, D.F. (Mexico)
2. Also at Center for Astronomy and Astrophysics, Shanghai Jiao Tong University, Shanghai 200240, China. (China)

We perform an exhaustive comparison among central galaxies from Sloan Digital Sky Survey catalogs in different local environments at 0.01 ≤ z ≤ 0.08. The central galaxies are separated into two categories: group centrals (host halos containing satellites) and field centrals (host halos without satellites). From the latter, we select two subsamples: isolated centrals and bright field centrals, both with the same magnitude limit. The stellar mass (M {sub s}) distributions of the field and group central galaxies are different, which explains why in general the field central galaxies are mainly located in the blue cloud/star-forming regions, whereas the group central galaxies are strongly biased to the red sequence/passive regions. The isolated centrals occupy the same regions as the bright field centrals since both populations have similar M {sub s} distributions. At parity of M {sub s}, the color and specific star formation rate (sSFR) distributions of the samples are similar, especially between field and group centrals. Furthermore, we find that the stellar-to-halo mass (M {sub s}-M {sub h}) relation of isolated galaxies does not depend on the color, sSFR, and morphological type. For systems without satellites, the M {sub s}-M {sub h} relation steepens at high halo masses compared to group centrals, which is a consequence of assuming a one-to-one relation between group total stellar mass and halo mass. Under the same assumption, the scatter around the M {sub s}-M {sub h} relation of centrals with satellites increases with halo mass. Our results suggest that the mass growth of central galaxies is mostly driven by the halo mass, with environment and mergers playing a secondary role.

• OSTI ID: 22356700
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 788; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CATALOGS
COLOR
COMPARATIVE EVALUATIONS
DISTRIBUTION
GALAXIES
MASS
PARITY
SATELLITES
SKY
STAR EVOLUTION
STARS