Modelling galaxy clustering: halo occupation distribution versus subhalo matching.
We model the luminosity-dependent projected and redshift-space two-point correlation functions (2PCFs) of the Sloan Digital Sky Survey (SDSS) Data Release 7 Main galaxy sample, using the halo occupation distribution (HOD) model and the subhalo abundance matching (SHAM) model and its extension. All the models are built on the same high-resolutionN-body simulations. We find that the HOD model generally provides the best performance in reproducing the clustering measurements in both projected and redshift spaces. The SHAM model with the same halo-galaxy relation for central and satellite galaxies (or distinct haloes and subhaloes), when including scatters, has a best-fitting χ2/dof around 2-3. We therefore extend the SHAM model to the subhalo clustering and abundance matching (SCAM) by allowing the central and satellite galaxies to have different galaxy-halo relations. We infer the corresponding halo/subhalo parameters by jointly fitting the galaxy 2PCFs and abundances and consider subhaloes selected based on three properties, the massMaccat the time of accretion, the maximum circular velocityVaccat the time of accretion, and the peak maximum circular velocityVpeakover the history of the subhaloes. The three subhalo models work well for luminous galaxy samples (with luminosity aboveL*). For low-luminosity samples, theVaccmodel stands out in reproducing the data, with theVpeakmodel slightly worse, while theMaccmodel fails to fit the data. We discuss the implications of the modelling results.
Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Shanghai 200030, China; Department of Physics and Astronomy, University of Utah, UT 84112, USA.
Hong
H
Guo
Department of Physics and Astronomy, University of Utah, UT 84112, USA.
Zheng
Z
Zheng
Astronomy and Physics Departments and Theoretical Astrophysics Center, University of California, Berkeley, CA 94720, USA.
Peter S
PS
Behroozi
Department of Astronomy, Case Western Reserve University, OH 44106, USA; Institute for Computational Cosmology, Department of Physics, University of Durham, South Road, Durham DH1 3LE, UK.
Idit
I
Zehavi
Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.
Chia-Hsun
CH
Chuang
Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.
Johan
J
Comparat
Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Campus of International Excellence UAM+CSIC, Cantoblanco, E-28049 Madrid, Spain.
Ginevra
G
Favole
Leibniz-Institut fur Astrophysik (AIP), An der Sternwarte 16, D-14482 Potsdam, Germany.
Stefan
S
Gottloeber
Astronomy Department, New Mexico State University, MSC 4500, PO Box 30001, Las Cruces, NM 880003-8001, USA; Severo Ochoa Associate Researcher at the Instituto de Fisica Teorica (UAM/CSIC), E-28049 Madrid, Spain.
Anatoly
A
Klypin
Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Campus of International Excellence UAM+CSIC, Cantoblanco, E-28049 Madrid, Spain; Instituto de Astrofísica de Andalucía (CSIC), Glorieta de la Astronomía, E-18080 Granada, Spain.
Francisco
F
Prada
Instituto de Física Teórica, (UAM/CSIC), Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain; Campus of International Excellence UAM+CSIC, Cantoblanco, E-28049 Madrid, Spain.
Sergio A
SA
Rodríguez-Torres
Department of Astronomy, Ohio State University, Columbus, OH 43210, USA; Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210, USA.
David H
DH
Weinberg
Departamento de Física Teórica, Universidad Autónoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.
Gustavo
G
Yepes
cosmology: observations; cosmology: theory; galaxies: distances and redshifts; galaxies: haloes; galaxies: statistics; large-scale structure of Universe