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On the local radio luminosity function of galaxies. I. The Virgo cluster
We cross-correlate the galaxies brighter than m_B=18 in the Virgocluster with the radio sources in the NVSS survey (1.4 GHz), resultingin 180 radio-optical identifications. We determine the radio luminosityfunction of the Virgo galaxies, separately for the early- andlate-types. Late-type galaxies develop radio sources with a probabilityproportional to their optical luminosity. In fact their radio/optical(R_B) distribution is gaussian, centered at log R_B ~ -0.5, i.e. theradio luminosity is ~ 0.3 of the optical one. The probability oflate-type galaxies to develop radio sources is almost independent oftheir detailed Hubble type, except for Sa (and S0+S0a) which are afactor of ~ 5 less frequent than later types at any R_B. Giantelliptical galaxies feed ``monster" radio sources with a probabilitystrongly increasing with mass. However the frequency of fainter radiosources is progressively less sensitive on the system mass. The faintestgiant E galaxies (M_B=-17) have a probability of feeding low power radiosources similar to that of dwarf E galaxies as faint as M_B=-13. Table~1is only available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| A Complete Redshift Survey to the Zwicky Catalog Limit in a 2^h X 15 deg Region around 3C 273
We compile 1113 redshifts (648 new measurements, 465 from theliterature) for Zwicky catalog galaxies in the region (-3.5d <= delta<= 8.5d, 11h5 <= alpha <= 13h5). We include redshifts for 114component objects in 78 Zwicky catalog multiplets. The redshift surveyin this region is 99.5% complete to the Zwicky catalog limit, m_Zw =15.7. It is 99.9% complete to m_Zw = 15.5, the CfA Redshift Survey(CfA2) magnitude limit. The survey region is adjacent to the northernportion of CfA2, overlaps the northernmost slice of the Las CampanasRedshift Survey, includes the southern extent of the Virgo Cluster, andis roughly centered on the QSO 3C 273. As in other portions of theZwicky catalog, bright and faint galaxies trace the same large-scalestructure.
| A Minnesota Automated Plate Scanner Catalog of Galaxies behind the Virgo Cluster and toward Its Antipode
We present a catalog of 1268 galaxies, essentially complete to B <=17.0, found by scanning glass copies of several fields of the originalPalomar Sky Survey using the Minnesota Automated Plate Scanner in itsisodensitometric mode (as opposed to the threshold densitometric modeused in the APS Catalog of the POSS I). In addition to the differentscanning mode, we have employed a different star-galaxy separationmethod and have visually inspected POSS prints to verify that each imageremaining in the catalog is nonstellar. The scanned fields aredistributed generally in two areas, one around the outskirts of theVirgo Cluster, the other toward the antipode of the cluster (but stillin the northern celestial hemisphere). The catalog gives the position ofthe center of each galaxy; estimates of the blue and red magnitudeswithin the outermost threshold crossing and of the blue magnitudeextrapolated to zero surface brightness; and the blue and red diametersof four ellipses fitted to the four threshold crossings (approximately23.8,23.6,23.2, and 22.7 mag arcsec 2 in blue, and 22.5,22.4,21.5, and21.2 mag arcsec^-2^ in red), and the ellipticities of those fourellipses. The catalog has served as a base from which to draw targetsfor a Tully-Fisher study of the Virgocentric infall velocity of theLocal Group.
| 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.
| Neutral hydrogen in small groups of galaxies
Neutral hydrogen in 36 pairs and small groups of galaxies was studiedusing the Arecibo radio telescope. Potential groups were selected fromthe Uppsala General Catalogue of Galaxies of Nilson (1973) by a simplealgorithm with the aims of determining or improving redshifts forgalaxies in possible groups and of mapping some of the larger galaxiesto determine their internal dynamics. The H I spectra are examined indetail and problems of confusion in these and previous observations areaddressed. A simple analysis of the groups' mean dynamical mass suggeststhat the mass determined from the galaxies' rotation is sufficient tobind them, but there may be important unmodeled selection orcontamination problems. A simple method for estimating errors of H Ivelocity measurements is also derived.
| Studies of the Virgo Cluster. II - A catalog of 2096 galaxies in the Virgo Cluster area.
The present catalog of 2096 galaxies within an area of about 140 sq degapproximately centered on the Virgo cluster should be an essentiallycomplete listing of all certain and possible cluster members,independent of morphological type. Cluster membership is essentiallydecided by galaxy morphology; for giants and the rare class of highsurface brightness dwarfs, membership rests on velocity data. While 1277of the catalog entries are considered members of the Virgo cluster, 574are possible members and 245 appear to be background Zwicky galaxies.Major-to-minor axis ratios are given for all galaxies brighter than B(T)= 18, as well as for many fainter ones.
| A radio continuum survey at 1.4 GHz of the galaxies in the Virgo region
Radio continuum observations made with the Westerbork Synthesis RadioTelescope at 1.4 GHz are presented for 274 galaxies in the Virgo Clusterregion. The observations are partly full syntheses and partly east-weststrip distributions. For the 55 detected galaxies the emission isseparated into central and extended components. A brief summary of theanalysis is also given.
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