2007/07/18 by Cinzia Di Porto, Luca Amendola · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1103/physrevd.77.083508
published as Phys.Rev.D77:083508,2008 · 9 pages
arxiv created 2007/07/18 · openalex publication_date 2008/04/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Many experiments in the near future will test dark energy through its effects on the linear growth of matter perturbations. It is therefore important to find simple and at the same time general parametrizations of the linear growth rate. We show that a simple fitting formula that generalizes previous expressions reproduces the growth function in models that allow for a growth faster than standard, as for instance in interacting or scalar-tensor models. We use data from galaxy and Lyman-\ensuremathα power spectra to constrain the linear growth rate. We find \ensuremathγ=0.6_\ensuremath-0.3+0.4 for the growth rate index and \ensuremathη=0.0_\ensuremath-0.2+0.3 for the additional growth parameter we introduce.