The galaxy-dark matter connection: A cosmological perspective

7th International Conference on Gravitation and Cosmology

More, S.^1 ; Van Den Bosch, F.^2 ; Cacciato, M.^3 ; More, A.^1 ; Mo, H.^4 ; Yang, X.^5

Kavli Institute for Cosmological Physics, University of Chicago, 933 East 56th Street, Chicago, IL 60637, United States^1

Department of Astronomy, Yale University, Box 208101, New Haven, CT 06520-8101, United States^2

Racah Institute of Physics, Hebrew University, Jerusalem 91904, Israel^3

Department of Astronomy, University of Massachusetts, Amherst MA 01003-9305, United States^4

Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Partner Group of MPA, Nandan Road 80, Shanghai 200030, China^5

关键词: Cosmological parameters;    Dark matter;    Galaxy bias;    Galaxy formations;    Luminosity functions;    Mass distribution;    Matrix analysis;    Sloan Digital Sky Survey;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/484/1/012042/pdf
DOI  :  10.1088/1742-6596/484/1/012042

来源: IOP

【 摘 要 】

We have presented a method that uses observations of galaxies to simultaneously constrain cosmological parameters, and the galaxy-dark matter connection (aka halo occupation statistics). The latter describes how galaxies are distributed over dark matter haloes, and is an imprint of the poorly understood physics of galaxy formation. A generic problem of using galaxies to constrain cosmology is that galaxies are a biased tracer of the mass distribution, and this bias is generally unknown. The great advantage of simultaneously constraining cosmology and halo occupation statistics is that this effectively allows cosmological constraints marginalized over the uncertainties regarding galaxy bias. We have used a combination of the analytical halo model and the conditional luminosity function to describe the galaxy-dark matter connection, which we have used to model the abundance, clustering and galaxy-galaxy lensing properties of the galaxy population. We have used a Fisher matrix analysis to gauge the complementarity of these different observables, and presented some preliminary results from an analysis based on data from the Sloan Digital Sky Survey. Our results are complementary to and perfectly consistent with the results from the WMAP mission, strengthening the case for a true 'concordance' cosmology.