Redshift-Space Distortions with the Halo Occupation Distribution II: Analytic Model
| dc.creator | Tinker, Jeremy L. | |
| dc.date | 2006-04-11 | |
| dc.date.accessioned | 2026-07-07T10:22:59Z | |
| dc.date.available | 2026-07-07T10:22:59Z | |
| dc.description | We present an analytic model for the galaxy two-point correlation function in redshift space. The model is constructed within the framework of the Halo Occupation Distribution (HOD), which quantifies galaxy bias on linear and non- linear scales. We model one-halo pairwise velocities by assuming that satellite galaxy velocities follow a Gaussian distribution with dispersion proportional to the virial dispersion of the host halo. Two-halo velocity statistics are a combination of virial motions and host halo motions. The velocity distribution function (DF) of halo pairs is a complex function with skewness and kurtosis that vary substantially with scale. Using a series of collisionless N-body simulations, we demonstrate that the shape of this DF is determined primarily by the distribution of local densities around a halo pair, and at fixed density the velocity DF is close to Gaussian and nearly independent of halo mass. We calibrate a model for the conditional probability function of densities around halo pairs on these simulations. With this model, the full shape of the halo velocity DF can be accurately calculated as a function of halo mass, radial separation, angle, and cosmology. The HOD approach to redshift-space distortions utilizes clustering data from linear to non-linear scales to break the standard degeneracies inherent in previous models of redshift-space clustering. The parameters of the occupation function are well constrained by real-space clustering alone, separating constraints on bias and cosmology. We demonstrate the ability of the model to separately constrain Omega_m, sigma_8, and galaxy velocity bias in models that are constructed to have the same value of beta at large scales as well as the same finger-of-god distortions at small scales. [Abridged] | |
| dc.description | 21 pages, submitted to MNRAS | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0604217 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0604217 | |
| dc.identifier | Mon.Not.Roy.Astron.Soc.374:477-492,2007 | |
| dc.identifier | doi:10.1111/j.1365-2966.2006.11157.x | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/175670 | |
| dc.subject | Astrophysics | |
| dc.title | Redshift-Space Distortions with the Halo Occupation Distribution II: Analytic Model | |
| dc.type | text |