Distribution function approach to redshift space distortions. Part V: perturbation theory applied to dark matter halos

Journal Article · Tue Oct 01 04:00:00 EDT 2013 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2013/10/053· OSTI ID:22282601

Vlah, Zvonimir; Seljak, Uroš ^[1]; Okumura, Teppei ^[2]; Desjacques, Vincent ^[3]

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1. Institute for Theoretical Physics, University of Zürich, Zürich (Switzerland)
2. Institute for the Early Universe, Ewha Womans University, Seoul, S. Korea (Korea, Republic of)
3. Département de Physique Théorique and Center for Astroparticle Physics (CAP) Université de Genéve, Genéve (Switzerland)

Numerical simulations show that redshift space distortions (RSD) introduce strong scale dependence in the power spectra of halos, with ten percent deviations relative to linear theory predictions even on relatively large scales (k < 0.1h/Mpc) and even in the absence of satellites (which induce Fingers-of-God, FoG, effects). If unmodeled these effects prevent one from extracting cosmological information from RSD surveys. In this paper we use Eulerian perturbation theory (PT) and Eulerian halo biasing model and apply it to the distribution function approach to RSD, in which RSD is decomposed into several correlators of density weighted velocity moments. We model each of these correlators using PT and compare the results to simulations over a wide range of halo masses and redshifts. We find that with an introduction of a physically motivated halo biasing, and using dark matter power spectra from simulations, we can reproduce the simulation results at a percent level on scales up to k ∼ 0.15h/Mpc at z = 0, without the need to have free FoG parameters in the model.

• OSTI ID: 22282601
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 10 Vol. 2013; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
COSMOLOGY
DENSITY
DISTRIBUTION FUNCTIONS
ENERGY SPECTRA
MASS
NONLUMINOUS MATTER
PERTURBATION THEORY
RED SHIFT
SPACE