| Abstract | New redshifts and magnitudes have been obtained at the Mount Stromlo and Siding Spring Observatories for many galaxies in the Shapley-Ames catalog south of 8 300. A subset of the material-multiplets, groups, and clusters of E and SO galaxies-is used to test again the isotropy of the Hubble expansion. Redshifts of 138 galaxies in 22 southern multiplets, groups, and clusters, and photoelectric UBVR magnitudes for 74 of the first few brightest galaxies in each aggregate give the following results. A) The color excess as a function of galactic latitude for southern galaxies increases less steeply toward the galactic plane than expected from galaxy counts, confirming an earlier result from northern data. The optical half-thickness is T 0 for IbI > 500. B) The absolute magnitude for first-ranked E galaxies is a very shallow function of richness for Nc48 > 20, but steepens for Nc48 < 20. This requires the luminosity function to be nearly vertical at the bright end. C) Deviations from the redshifi-magnitude (Hubble) diagram are uncorrelated with either supergalactic longitude, with Rubin-Ford-Rubin (RFR) regions, or with the apex of the RubinFord proposed motion of the Local Group. Limits of less than 8 percent can be put on a possible perturbation of the local Hubble rate for the center and anticenter supergalactic hemispheres, using E groups with velocities smaller than 3000 km 1 D) A crude estimate of q0, found from the upper limit of 8H!H0 < 0.08 (a) for any possible velocity perturbation for the E groups in the presence of a density contrast of 8p/p = 3.4 + 0.2 (a), is q0 <0.02 + 0.02, from the idealized model of Silk. But the E groups here are generally beyond the Virgo cluster, giving this determination low weight; reanalysis of the spiral data puts an upper limit of 8H/H0 = 0.40 + 0.09 (a), if the uncertain data for field spirals are adopted uncritically, giving q0 <0.28 + 0.08(a). These low values of q0 agree with similar low values from five other methods summarized in the paper. Subject headings: cosmology - galaxies, clusters of - galaxies, photometry of - redshifts |
