Power Spectra for Cold Dark Matter and Its Variants


Eisenstein DJ, Hu W. Power Spectra for Cold Dark Matter and Its Variants. The Astrophysical Journal. 1999;511 :5-15.

Date Published:

January 1, 1999


The bulk of recent cosmological research has focused on the adiabaticcold dark matter model and its simple extensions. Here we present anaccurate fitting formula that describes the matter transfer functions ofall common variants, including mixed dark matter models. The result is afunction of wavenumber, time, and six cosmological parameters: themassive neutrino density, number of neutrino species degenerate in mass,baryon density, Hubble constant, cosmological constant, and spatialcurvature. We show how observational constraints-e.g., the shape of thepower spectrum, the abundance of clusters and damped Lyalpha systems,and the properties of the Lyalpha forest-can be extended to a wide rangeof cosmologies, which includes variations in the neutrino and baryonfractions in both high-density and low-density universes.