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Redshift-Distance Survey of Early-Type Galaxies. I. The ENEARc Cluster Sample
This paper presents data on the ENEARc subsample of the larger ENEARsurvey of nearby early-type galaxies. The ENEARc galaxies belong toclusters and were specifically chosen to be used for the construction ofa Dn-σ template. The ENEARc sample includes newmeasurements of spectroscopic and photometric parameters (redshift,velocity dispersion, line index Mg2, and the angular diameterdn), as well as data from the literature. New spectroscopicdata are given for 229 cluster early-type galaxies, and new photometryis presented for 348 objects. Repeat and overlap observations withexternal data sets are used to construct a final merged catalogconsisting of 640 early-type galaxies in 28 clusters. Objectivecriteria, based on catalogs of groups of galaxies derived from completeredshift surveys of the nearby universe, are used to assign galaxies toclusters. In a companion paper, these data are used to construct thetemplate Dn-σ distance relation for early-typegalaxies, which has been used to estimate galaxy distances and derivepeculiar velocities for the ENEAR all-sky sample. Based on observationsat Complejo Astronomico El Leoncito, operated under agreement betweenthe Consejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; Cerro Tololo Inter-American Observatory,National Optical Astronomical Observatory, which is operated by theAssociation of Universities for Research in Astronomy, Inc., undercooperative agreement with the National Science Foundation; the EuropeanSouthern Observatory (ESO), partially under the ESO-ON agreement; theFred Lawrence Whipple Observatory; the Observatório do Pico dosDias, operated by the Laboratório Nacional de Astrofísicaand the MDM Observatory at Kitt Peak.
| A catalogue of Mg_2 indices of galaxies and globular clusters
We present a catalogue of published absorption-line Mg_2 indices ofgalaxies and globular clusters. The catalogue is maintained up-to-datein the HYPERCAT database. The measurements are listed together with thereferences to the articles where the data were published. A codeddescription of the observations is provided. The catalogue gathers 3541measurements for 1491 objects (galaxies or globular clusters) from 55datasets. Compiled raw data for 1060 galaxies are zero-point correctedand transformed to a homogeneous system. Tables 1, 3, and 4 areavailable in electronic form only at the CDS, Strasbourg, via anonymousftp 130.79.128.5. Table 2 is available both in text and electronic form.
| Galaxy clusters in the Perseus-Pisces region. I - Spectroscopic and photometric data for early-type galaxies
We present new spectroscopic and photometric data for 137 early-typegalaxies in nine clusters and for a set of nearby standard galaxies. Ourspectroscopic data comprise radial velocities, central velocitydispersions, and magnesium line strength indices. We demonstrate thatour new velocity dispersion data can be brought into consistency withthe standard system, to an uncertainty of percent 0.01 dex. From R-bandCCD photometry, we derive the effective diameter, the mean surfacebrightness within the effective diameter, and an R-band diameterequivalent to the Dn parameter of Dressler et al. Internal comparisonsindicate an average error of 0.005 in each measurement of log Dn. Thephotometric data can be brought on to a system consistent with externaldata at the level of 0.5 per cent in distance.
| An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| Peculiar velocities of clusters in the Perseus-Pisces supercluster
Photometry is presented for spiral galaxies in five clusters of galaxiesin the direction of the Perseus-Pisces supercluster. The 21 cmobservations of these galaxies by Giovanelli et al. (1982, 1986) areemployed to measure distances of these clusters by means of theTully-Fisher relation. Most of these are in fact more distant than thesupercluster and have peculiar velocities averaging 400 km/s. This isbroadly in agreement with the earlier result of Willick (1990, 1991) whoanalyzed a large field sample. A local model in which galaxies areinfalling to two mass concentrations, one in Perseus-Pisces and one inHydra-Centaurus, fits the data at least as well as bulk flow. Thepresent data leave both these possibilities open.
| A 21 CM survey of the Pisces-Perseus supercluster. IV - Addenda to the declination zone 21.5 deg to 33.5 deg
Using the 305-m Arecibo telescope, 21-cm line data on 472 disk galaxiesin the Pisces-Perseus supercluster have been obtained. Data on galaxiessmaller than 1 arcmin are presented for the declination strips coveredin previous studies (Giovanelli and Haynes, 1985 and Giovanelli et al.,1986). Tables of the 21-cm line data for this region are presented.
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