Nonlinear corrections to the cosmological matter power spectrum and scale-dependent galaxy bias: implications for parameter estimation
| dc.creator | Hamann, Jan | |
| dc.creator | Hannestad, Steen | |
| dc.creator | Melchiorri, Alessandro | |
| dc.creator | Wong, Yvonne Y. Y. | |
| dc.date | 2008-04-11 | |
| dc.date | 2008-09-08 | |
| dc.date.accessioned | 2026-07-07T11:49:46Z | |
| dc.date.available | 2026-07-07T11:49:46Z | |
| dc.description | We explore and compare the performances of two nonlinear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-LCDM cosmologies. The first model is the well known Q model, first applied in the analysis of 2dFGRS data. The second, the P model, is inspired by the halo model, in which nonlinear evolution and scale-dependent biasing are encapsulated in a single non-Poisson shot noise term. We find that while both models perform equally well in providing adequate correction for a range of galaxy clustering data in standard LCDM cosmology and in extensions with massive neutrinos, the Q model can give unphysical results in cosmologies containing a subdominant free-streaming dark matter whose temperature depends on the particle mass, e.g., relic thermal axions, unless a suitable prior is imposed on the correction parameter. This last case also exposes the danger of analytic marginalisation, a technique sometimes used in the marginalisation of nuisance parameters. In contrast, the P model suffers no undesirable effects, and is the recommended nonlinear correction model also because of its physical transparency. | |
| dc.description | 21 pages, 8 figures, uses iopart.cls; v2: 22 pages, matches published version | |
| dc.identifier | https://arxiv.org/abs/0804.1789 | |
| dc.identifier | http://arxiv.org/abs/0804.1789 | |
| dc.identifier | JCAP0807:017,2008 | |
| dc.identifier | doi:10.1088/1475-7516/2008/07/017 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/203351 | |
| dc.subject | Astrophysics | |
| dc.title | Nonlinear corrections to the cosmological matter power spectrum and scale-dependent galaxy bias: implications for parameter estimation | |
| dc.type | text |