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The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
| Total Magnitudes of Virgo Galaxies. II. An Investigation into the mp Scale of Volume I of Zwicky et al.'s Catalogue of Galaxies and of Clusters of Galaxies
We investigate the photographic-magnitude (mp) scale ofVolume I of the Catalogue of Galaxies and of Clusters of Galaxies forgalaxies in the Virgo direction. It is found that for 11.5 <= Bt <14 5, the mp values listed correspond very closely (with ascatter of only 0.16 magnitude) to blue magnitudes measured to theμB = 24 4 isophote. If mp values need to beused as estimates of total blue magnitude the scatter is 0.27 magnitudeover the same range in Bt and the mean offset ismp-Bt=0 28 magnitude. However, a serious scaleerror at the bright end causes both the isophotal and total luminositiesof galaxies brighter than Bt~11.5 to be severelyunderestimated. At the faint end there also appears to be a significantscale error. This causes galaxy luminosities to be seriouslyoverestimated faintward of Bt ~ 14.5. We demonstrate thatthis is a real effect based on a detailed galaxy-by-galaxy study of thecatalogue's completeness down to Bt= 17.0. The catalogue isfound only to be complete to Bt ~ 14.7 whilst its degree ofincompleteness is found to be relatively constant at the 30% level overthe range 14.75 <= Bt < 15.75. Most of the missingobjects are found to be elliptical galaxies and so late-type objects areover-represented at the faint end.
| X-ray luminosities of galaxies in groups
We have derived the X-ray luminosities of a sample of galaxies ingroups, making careful allowance for contaminating intragroup emission.The LX:LB and LX:LFIRrelations of spiral galaxies in groups appear to be indistinguishablefrom those in other environments, however the elliptical galaxies fallinto two distinct classes. The first class is central-dominant groupgalaxies, which are very X-ray luminous and may be the focus of groupcooling flows. All other early-type galaxies in groups belong to thesecond class, which populates an almost constant band ofLX/LB over the range9.8
| Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| 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
| The ``Virgo photometry catalogue''; a catalogue of 1180 galaxies in the direction of the Virgo Cluster's core
We present a new catalogue of galaxies in the direction of the VirgoCluster's core: the Virgo Photometry Catalogue (VPC)*. This cataloguecontains 1180 galaxies (including background objects) within a 23square-degree area of the sky centred on R.A._{1950.0} = 12h 26m anddec._{1950.0} = 13(deg) 08'. The VPC galaxy sample comprises ofnon-stellar objects brighter than B_J25 = 19.0; thecompleteness limits being B_J25 ~18.5 for the northern halfof the survey area and B_J25 ~18.0 for the southern half.Independently-calibrated photographic surface photometry is presentedfor over 1000 galaxies in the U, B_J and R_C bands. Parameters listedfor catalogued galaxies include: equatorial coordinates, morphologicaltypes, surface-brightness profile parameters (which preserve themajority of the original surface photometry information), U, B_J &R_C isophotal magnitudes, B_J and [transformed] B total magnitudes,(U-B_J) and (B_J-R_C) equal-area and total colours, apparent angularradii, ellipticities, position angles, heliocentric radial velocitiesand alternative designations. All total magnitudes and total colours areextrapolated according to a new system denoted t in order to distinguishit from the T system already in use. The VPC is based primarily on four(one U, two B_J and one R_C) UK-Schmidt plates, all of which weredigitised using the Royal Observatory Edinburgh's (ROE) COSMOS measuringmachine. All magnitudes, colours and surface-brightness parameters arederived from numerical integrations of segmented plate-scan data, exceptfor (in 109 cases) saturated or (in 51 cases) inextricably-mergedimages; our segmentation software being able to cope with the vastmajority of image mergers. * Appendices B, C and E, which contain thesurface photometry, the main catalogue and the summary cataloguerespectively, are only available in electronic form. They can beobtained from La Centre des Donees astronomiques de Strasbourg (CDS) viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html.
| 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.
| The UV properties of normal galaxies. III. Standard luminosity profiles and total magnitudes.
In the previous papers of this series we collected and reduced to thesame system all the available photometric data obtained in theultraviolet (UV) range for normal (i.e. non active) galaxies. Here weuse these data to derive standard UV luminosity profiles for threemorphological bins (E/S0; Sa/Sb; Sc/Sd) and extrapolated totalmagnitudes for almost 400 galaxies. We find that: 1) the UV growthcurves are well matched by the B-band revised standard luminosityprofiles, once a proper shift in the effective radius is applied, and 2)the UV light in early-type galaxies is more centrally concentrated thanthe visible light.
| The UV properties of normal galaxies. II. The ``non-IUE'' data.
In the last decade several satellite and balloon borne experiments havecollected a large number of ultraviolet fluxes of normal galaxiesmeasured through apertures of various sizes and shapes. We havehomogenized this data set by deriving scale corrections with respect toIUE. In a forthcoming paper these data will be used to derive standardluminosity profiles and total magnitudes.
| Global properties of infrared bright galaxies
Infrared flux densities of 182 galaxies, including 50 galaxies in theVirgo cluster, were analyzed using IRAS data for 12, 25, 60, and 100microns, and the results were compared with data listed in the PointSource Catalog (PSC, 1985). In addition, IR luminosities, L(IRs),colors, and warm dust masses were derived for these galaxies and werecompared with the interstellar gas masses and optical luminosities ofthe galaxies. It was found that, for galaxies whose optical diametermeasures between 5 and 8 arcmin, the PSC flux densities areunderestimated by a factor of 2 at 60 microns, and by a factor of 1.5 at100 microns. It was also found that, for 49 galaxies, the mass of warmdust correlated well with the H2 mass, and that L(IR) correlated withL(H-alpha), demonstrating that the L(IR) measures the rate of starformation in these galaxies.
| An infrared-optical study of IRAS point sources in the Virgo region
Optical identifications for 199 of the 206 IRAS point sources in a 113sq deg area centered on the Virgo cluster are made using four deepIIIa-J plates obtained with the 1.2-m UK Schmidt Telescope. Only 4percent of the E and S0 galaxies brigher than B = 16 are detected, ascompared with 44 percent of the Sc galaxies. Infrared properties of theVirgo cluster are found to be similar to those of field galaxies atsimilar redshifts. Such IRAS galaxies are typical spirals with B of lessthan about 14, infrared to optical luminosity ratios of about 1, andinfrared luminosities of about 10 to the 9th solar luminosities,properties which are independent of neutral hydrogen content for theVirgo cluster galaxies. Data suggest that the optically faint galaxieshave L(IR) of greater than 10 to the 12th solar luminosities.
| HI-observations of galaxies in the Virgo cluster of galaxies. I - The data
New H I-data for a large number of bright galaxies inside the 10 degradius area of the Virgo cluster of galaxies have been obtained with the100 m radiotelescope at Effelsberg. A total of 234 galaxies was observedfor the first time. Among them, 53 have been detected providing newaccurate radial velocities. Data from the literature have been compiled.Together with the new data, they form a (nearly homogeneous) set of H Iobservations for more than 450 galaxies.
| 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.
| Middle-ultraviolet photometry of Virgo cluster galaxies
Photographic photometry of Virgo cluster galaxies has been performed ina wavelength band extending from 1620-3200 A using sounding rockettechniques. The observational results are middle ultraviolet magnitudes,U2421, or faint limits for U2421, for 201 galaxies within 5.5 arcmin ofthe cluster center. A strong negative correlation is found between U2421- V and V for all observed S0 galaxies and a similar but weakercorrelation for the observed ellipticals. No such correlation is foundfor spiral galaxies regardless of their projection angles on the sky.The measured colors are generally compatible with colors computed frompreviously generated composite spectra.
| Eighth list of compact galaxies .
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975AJ.....80..545Z&db_key=AST
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