Maximum Likelihood Comparison of Tully‐Fisher and Redshift Data. II. Results from an Expanded Sample

Abstract

Received; accepted This is the second in a series of papers in which we compare Tully-Fisher (TF) data from the Mark III Catalog with predicted peculiar velocities based on the IRAS galaxy redshift survey and gravitational instability theory, using a rigorous maximum likelihood method called VELMOD. In Paper I (Willick et al. 1997b), we applied the method to a czLG ≤ 3000 km s −1, 838-galaxy TF sample and found βI = 0.49 ± 0.07, where βI ≡ Ω 0.6 /bI and bI is the linear biasing parameter for IRAS galaxies. In this paper we increase the redshift limit to czLG = 7500 km s −1, thereby enlarging the sample to 1876 galaxies. The expanded sample now includes the W91PP and CF subsamples of the Mark III catalog, in addition to the A82 and MAT subsamples already considered in Paper I. We implement VELMOD using both the forward and inverse forms of the TF relation, and allow for a more general form of the quadrupole velocity residual detected in Paper I. We find βI = 0.50 ±0.04 (1 σ error) at 300 km s −1 smoothing of the IRAS-predicted velocity field. The fit residuals are spatially incoherent for βI = 0.5, indicating that the IRAS plus