New Velocity Dispersions and Photometry for E and S0 Galaxies in the Great Attractor

摘要: New spectroscopy and photometry have been obtained for 136 elliptical S0 galaxies in the direction of large-scale streaming flow attributed to great attractor. Measurements central velocity dispersion (sigma), total B magnitudes B(T), photometric parameter Dn, absorption-line index Mg2 are presented. Both internal external comparisons indicate that measurements log sigma accurate 0.05 dex, B(T) 0.15 mag, Dn 0.015 0.017 mag. These data used by Dressler Faber (1990) estimate distances these via Dn-sigma relation. It is shown this paper Dn-Mg2 relation also predicts same trends peculiar with distance, but less accuracy. The relative accuracy other distance indicators discussed. 23 refs.