Redshift-distance survey of early-type galaxies. I. Sample selection, properties, and completeness

This is the first in a series of papers describing the recently completed a ll-sky redshift-distance survey of Early-type NEARby galaxies (ENEAR) carri ed out for peculiar velocity analysis. The sample is divided into two parts and consists of 1607 elliptical and lenticular galaxies with cz less than or equal to 7000 km s(-1) and with blue magnitudes brighter than m(B), = 14 .5 (ENEARm) and of galaxies in clusters (ENEARc). Galaxy distances based on the D-n-sigma and fundamental plane (FP) relations are now available for 1 359 and 1107 ENEARm galaxies, respectively, with roughly 80% based on new d ata gathered by our group. The D-n-sigma and FP template distance relations are derived by combining 569 and 431 galaxies in 28 clusters, respectively , of which about 60% are based on our new measurements. To date the ENEAR survey has accumulated 2200 R-band images yielding photom etric parameters for 1398 galaxies and 2300 spectra yielding 1745 measureme nts of central velocity dispersions and spectral line indices for 1210 gala xies. In addition, there are some 1834 spectra of early-type galaxies avail able in the Southern Sky Redshift Survey (SSRS+SSRS2) database, out of whic h roughly 800 galaxies yield high-quality measurements of velocity dispersi ons and spectral line indices, bringing the total number of galaxies with a vailable spectral information to about 2000. Combined with measurements pub licly available, a catalog has been assembled comprising similar to 4500 me asurements of central velocity dispersions for about 2800 galaxies, similar to 3700 measurements of photometric parameters for about 2000 galaxies, an d distances for about 1900 galaxies. This extensive database provides infor mation on galaxies with multiple observations from different telescope/inst rument configurations and from different authors. These overlapping data ar e used to derive relations to transform all available measurements into a c ommon system, thereby ensuring the homogeneity of the database. The ENEARm redshift-distance survey extends the earlier work of the 7S and the recent Tully-Fisher surveys sampling a comparable volume. In subsequent papers of this series we intend to use the ENEAR sample by itself or in co mbination with the I-band field spiral (SFI) Tully-Fisher survey to analyze the properties of the local peculiar velocity field and to test how sensit ive the results are to the different sampling of the galaxy distribution an d to the distance relation used. We also anticipate that the homogeneous da tabase assembled will be used for a variety of other applications and serve as a benchmark for similar studies at high redshift.