Open AccessThe dependence of clustering on galaxy properties
Author(s) -
Li Cheng,
Kauffmann Guinevere,
Jing Y. P.,
White Simon D. M.,
Börner Gerhard,
Cheng F. Z.
Publication year - 2006
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2006.10066.x
Subject(s) - physics , astrophysics , galaxy , stellar mass , luminosity , sky , redshift , dark matter , luminosity function , cluster analysis , astronomy , star formation , statistics , mathematics
We use a sample of ∼200 000 galaxies drawn from the Sloan Digital Sky Survey (SDSS) with 0.01 < z < 0.3 and −23 < M 0.1 r< −16 to study how clustering depends on properties such as stellar mass ( M * ) , colour ( g − r ), 4000‐Å break strength ( D 4000 ), concentration index ( C ), and stellar surface mass density (μ * ) . Our measurements of w p ( r p ) as a function of the r ‐band luminosity are in excellent agreement with the previous two‐degree Field Galaxy Redshift Survey and SDSS analyses. We compute w p ( r p ) as a function of stellar mass and we find that more‐massive galaxies cluster more strongly than less‐massive galaxies, with the difference increasing above the characteristic stellar mass M * of the Schechter mass function. We then divide our sample according to colour, 4000‐Å break strength, concentration and surface density. As expected, galaxies with redder colours, larger 4000‐Å break strengths, higher concentrations and larger surface mass densities cluster more strongly. The clustering differences are largest on small scales and for low‐mass galaxies. At fixed stellar mass, the dependences of clustering on colour and 4000‐Å break strength are similar. Different results are obtained when galaxies are split by concentration or surface density. The dependence of w p ( r p ) on g − r and D 4000 extends out to physical scales that are significantly larger than those of individual dark matter haloes (>5 h −1 Mpc) . This large‐scale clustering dependence is not seen for the parameters C or μ * . On small scales ( <1 h −1 Mpc), the amplitude of the correlation function is constant for ‘young’ galaxies with 1.1 < D 4000 < 1.5 and a steeply rising function of age for ‘older’ galaxies with D 4000 > 1.5 . In contrast, the dependence of the amplitude of w p ( r p ) on concentration on scales less than 1 h −1 Mpc is strongest for disc‐dominated galaxies with C < 2.6. This demonstrates that different processes are required to explain environmental trends in the structure and in the star formation history of galaxies.