Mixed Cold-Hot Dark Matter Model with Falling and Quasi-flat Initial Perturbation Spectra

Abstract

view Abstract Citations (54) References (43) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Mixed Cold-Hot Dark Matter Model with Falling and Quasi-flat Initial Perturbation Spectra Pogosyan, Dmitri Yu. ; Starobinsky, Alexei A. Abstract The mixed cold-hot dark matter cosmological model (CHDM) withΩ tot = 1 and a falling power-law initial spectrum of Gaussian adiabatic perturbations (n > 1) is tested using recent observational data. It is shown that its fit to the data becomes worse with the growth of n-1 and may be considered as unreasonable for n> 1.1 for all possible values of the Hubble constant. Thus, the CHDM model with a falling initial spectrum is worse than the same model with the approximately flat (|n-1| <0.1) spectrum. On the other hand, the CHDM model provides a rather good fit to the data if n lies in the range (0.9-1.0), the Hubble constant H0 < 60 km s-1 Mpc-1 (H0 < 55 for n = 1) and the neutrino energy density Ω < 0.25. So, the CHDM model offers the best possibility for the realization of the simplest variants of the inflationary scenario having the effective slope n ≍ (0.95-0.97) between galaxy and horizon scales, including a modest contribution of primordial gravitational wave background to large-angle ΔT/T fluctuations of the cosmic microwave background (resulting in the increase of their total rms amplitude by 5%-10% expected in some variants). A classification of cosmological models according to the number of fundamental parameters used to fit observational data is presented, too. Publication: The Astrophysical Journal Pub Date: July 1995 DOI: 10.1086/175890 arXiv: arXiv:astro-ph/9409074 Bibcode: 1995ApJ...447..465P Keywords: COSMOLOGY: LARGE-SCALE STRUCTURE OF UNIVERSE; COSMOLOGY: DARK MATTER; COSMOLOGY: OBSERVATIONS; COSMOLOGY: THEORY; Astrophysics E-Print: 18 pages, LaTeX file, YITP/U-94-26, postscript figures on request full text sources arXiv | ADS |