Redshift-distance survey of early-type galaxies: Spectroscopic data

We present central velocity dispersions and Mg₂ line indices for an all-sky sample of ∼1178 elliptical and S0 galaxies, of which 984 had no previous measures. This sample contains the largest set of homogeneous spectroscopic data for a uniform sample of elliptical galaxies in the nearby universe. These galaxies were observed as part of the ENEAR project, designed to study the peculiar motions and internal properties of the local early-type galaxies. Using 523 repeated observations of 317 galaxies obtained during different runs, the data are brought to a common zero point. These multiple observations, taken during the many runs and different instrumental setups employed for this project, are used to derive statistical corrections to the data and are found to be relatively small, typically ≲ 5% of the velocity dispersion and 0.01 mag in the Mg₂ line strength. Typical errors are about 8% in velocity dispersion and 0.01 mag in Mg₂, in good agreement with values published elsewhere.