Small-Scale Perturbations in a General Mixed Dark Matter Cosmology
Abstract
For a universe with massive neutrinos, cold dark matter, and baryons, we solve the linear perturbation equations analytically in the small-scale limit and find agreement with numerical codes at the 1%-2% level. The inclusion of baryons, a cosmological constant, or spatial curvature reduces the small-scale power and tightens limits on the neutrino density from observations of high-redshift objects. Using the asymptotic solution, we investigate neutrino infall into potential wells and show that it can be described on all scales by a growth function that depends on time, wavenumber, and cosmological parameters. The growth function may be used to scale the present-day transfer functions back in redshift. This allows us to construct the time-dependent transfer function for each species from a single master function that is independent of time, cosmological constant, and curvature.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1998
- DOI:
- 10.1086/305585
- arXiv:
- arXiv:astro-ph/9710216
- Bibcode:
- 1998ApJ...498..497H
- Keywords:
-
- COSMOLOGY: THEORY;
- COSMOLOGY: DARK MATTER;
- COSMOLOGY: LARGE-SCALE STRUCTURE OF UNIVERSE;
- Cosmology: Theory;
- Cosmology: Dark Matter;
- Cosmology: Large-Scale Structure of Universe;
- Astrophysics
- E-Print:
- Submitted to ApJ