ENEAR Redshift-Distance Survey: Cosmological Constraints

Abstract

We present an analysis of the ENEAR sample of peculiar velocities of elliptical galaxies, obtained with D_n-sigma distances. We use the velocity correlation function to analyze the statistics of the field-object's velocities, while the analysis of the cluster data is based on the estimate of their rms peculiar velocity, Vrms. The statistics of the model velocity field is parameterized by the amplitude, eta_8=sigma_8 Omega_m^{0.6}, and by the shape parameter, Gamma. From the velocity correlation statistics we obtain eta_8=0.51{-0.09}{+0.24} for Gamma=0.25 at the 2sigma level. Even though less constraining, a consistent result is obtained by comparing the measured Vrms of clusters to linear theory predictions. For Gamma=0.25 we find eta_8=0.63{-0.19}{+0.22}$ at 1sigma. Overall, our results point toward a statistical concordance of the cosmic flows traced by spirals and early-type galaxies, with galaxy distances estimated using TF and D_n-sigma distance indicators, respectively.