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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.
| The Arizona-New Mexico Spectroscopic Survey of Galaxies. I. Data for the Western End of the Perseus Supercluster
We present new optical spectroscopic data for 347 galaxies in the regionof the Perseus supercluster. The new data were obtained using theSteward Observatory 2.3 m telescope and cover the whole optical window.Included are redshifts (for 345 objects), absorption-line equivalentwidths, a continuum index measuring the 4000 Å break, andemission-line flux ratios. After 11 objects are rejected for being toofaint and redshifts for 26 objects are added from the literature, wearrive at a complete sample of 361 galaxies. The distribution ofredshifts for the whole sample is examined, and we show the relationshipof the continuum index to morphology.
| 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.
| The Universality of the Fundamental Plane of E and S0 Galaxies: Spectroscopic Data
We present central velocity dispersion measurements for 325 early-typegalaxies in eight clusters and groups of galaxies, including newobservations for 212 galaxies. The clusters and groups are the A262,A1367, Coma (A1656), A2634, Cancer, and Pegasus Clusters and the NGC 383and NGC 507 Groups. The new measurements were derived frommedium-dispersion spectra that cover 600 Å centered on the Mg I btriplet at lambda ~ 5175 Å. Velocity dispersions were measuredusing the Tonry & Davis cross-correlation method, with a typicalaccuracy of 6%. A detailed comparison with other data sources is made.
| The Universality of the Fundamental Plane of E and S0 Galaxies: Sample Definition and I-Band Photometric Data
As part of a project to compare the fundamental plane and Tully-Fisherdistance scales, we present here I-band CCD photometry for 636early-type galaxies in eight clusters and groups of galaxies. These arethe A262, A1367, Coma (A1656), A2634, Cancer and Pegasus Clusters, andthe NGC 383 and NGC 507 Groups. Sample selection, cluster properties,and cluster membership assignment criteria are discussed. We presentphotometric parameters that are used in the fundamental plane relation,the effective radius r_e, and the effective surface brightness mu_e, asderived from a r^1/4 fit to the observed radial photometric profile ofeach galaxy. A comparison with similar data found in the literature forthe Coma Cluster shows that large systematic uncertainties can beintroduced in the measurement of r_e and mu_e by the particular methodused to derive those parameters. However, the particular combination ofthese two parameters that enters in the fundamental plane relation is aquantity that can be measured with high accuracy.
| Galaxy Alignments in the Pisces-Perseus Supercluster Revisited
A search for preferential galaxy alignments in the Pisces-PerseusSupercluster (PPS) is made using the Minnesota Automated Plate ScannerPisces-Perseus Survey (MAPS-PP). The MAPS-PP is a catalog of ~1400galaxies with a (roughly) isophotal diameter greater than 30"constructed from digitized scans of the blue and red plates of thePalomar Observatory Sky Survey covering the PPS. This is the largestsample of galaxies applied to a search of galaxy alignments in thissupercluster, and it has been used in combination with previouslypublished redshifts to construct the deepest PPS galaxy luminosityfunction to date. While previous studies have relied extensively oncatalogs with visually estimated parameters for both sample selectionand determination of galaxy orientation, the MAPS-PP uses selectioncriteria and measurements that are entirely machine and computer based.Therefore, it is not susceptible to some of the biases, such as thediameter inclination effect, known to exist in some other galaxycatalogs. The presence of anisotropic galaxy distributions is determinedby use of the Kuiper statistic, a robust alternative to the chi^2statistic more traditionally used in these studies. Three statisticallysignificant anisotropic distributions are observed. The reddest galaxiesare observed to be oriented preferentially perpendicular to the locallarge-scale structure. The bluest galaxies near the supercluster planeare observed to have an anisotropic position angle distribution.Finally, a weak trend for the median position angle of color-selectedgalaxy subsamples to ``twist'' with increasing distance from the PPSplane is observed. These position angle distribution anisotropies areweak and are not consistent with any single primordial or modern-eragalaxy alignment mechanism, although a mixture of such mechanisms is notruled out.
| The Relative Distance Between the Clusters of Galaxies A2634 and Coma
The Tully-Fisher (TF) and Fundamental Plane (FP) relations are used toobtain two independent estimates of the relative distance between theclusters A2634 and Coma. Previously published studies of A2634 showed alarge discrepancy between the distance estimates obtained with the TFand the \dns\ relations, questioning the reliability ofredshift-independent distances obtained using these relations. Becauseof the importance of this issue, we have obtained new distance estimatesfor A2634, based on much larger samples than previously used, andselected according to rigorous membership criteria. New I band CCDphotometry for 175 galaxies, new 21 cm observations of 11 galaxies, andnew velocity dispersion measurements for 62 galaxies are used togetherwith previously published data in building these samples. As part of alarger project to compare the TF and FP distance-scales, we haveobtained a new FP template using for the first time I band photometry.The template is derived using a sample of 109 E and S0 galaxies that aremembers of the Coma cluster. Its parameters are in very good agreementwith recent determinations of the FP obtained at shorter wavelengths.The uncertainty with which the FP can provide peculiar velocityestimates for single galaxies is =~ 0.43 mag in the distance modulus, or20% of the distance. This uncertainty is slightly larger than thetypical uncertainty that characterizes TF estimates. However thisdisadvantage is partly compensated by the fact that the sampleincompleteness bias has a less severe effect on FP cluster distanceestimates than it has on the corresponding TF distance estimates. Also,cluster membership is more readily established for early-type objectsthan for spirals. After the appropriate corrections for sampleincompleteness have been taken into account, we find the TF and FPdistance estimates to be in good agreement, both indicating that A2634has a negligibly small peculiar velocity with respect to the CosmicMicrowave Background reference frame. Because of the high accuracy withwhich the two distance estimates have been obtained, their agreementstrongly supports the universality of the TF and FP relations, andtherefore their reliability for the estimate of redshift-independentdistances.
| 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 spatial distribution, kinematics, and dynamics of the galaxies in the region of Abell 2634 and 2666
A total of 663 galaxies with known redshifts in a 12 deg x 12 deg fieldcentered on A2634, including 211 new measurements, are used to study indetail the structure of the region. In it we find six main galaxyconcentrations: the nearby clusters A2634 and A2666, two groups in thevicinity of A2634, and two distant clusters at approximately 18,000(A2622) and approximately 37,000 km/s seen in projection near the coreof A2634. For A2634, the most richly sampled of those concentrations, weare able to apply strict cluster membership criteria. Two samples - onecontaining 200 galaxies within 2 deg from the cluster center and asecond, magnitude-limited, of 118 galaxies within the central halfdegree - are used to examine the structure, kinematics, dynamics, andmorphological segregation of the cluster. We show that early typegalaxies appear to be a relaxed system, while the spiral populationeschews the center of the cluster and exhibits both a multimodalvelocity distribution and a much larger velocity dispersion that theellipticals. We propose that the spiral galaxies of A2634 represent adynamically young cluster population. For the galaxy component of A2634,we find no evidence of significant substructure in the central regions.We also conclude that the adoption of lenient membership criteria thatignore the dynamical complexity of A2634 are unlikely to be responsiblefor the conflicting results reported on the motion of this cluster withrespect ot the CMB. The kinematical and dynamical analysis is extendedto A2634's close companion, A2666, and the two distant backgroundclusters.
| The Dynamics of the Galaxy Cluster Abell 2634
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993ApJ...416...36P&db_key=AST
| A list of some corrections to Zwicky's Catalogue of Galaxies and Clusters of Galaxies
Not Available
| HI observations of galaxies in nearby Zwicky clusters
The results of a long term project of H I observations of galaxieswithin the boundaries of nearby Zwicky clusters are presented. Thedetection rate is rather low (233 out of 618, i.e., 38 percent) ascompared to other surveys carried out recently. Most of the radialvelocities of the detected galaxies are new determinations. The largespread in radial velocities for many of these clusters is a strongindication for the presence of several foreground and/or backgroundgalaxies.
| 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.
| A 21 CM survey of the Pisces-Perseus supercluster. II - The declination zone +21.5 to +27.5 degrees
Neutral-hydrogen 21-cm line spectra and derived parameters are presentedfor a sample of spiral galaxies in the region bounded by an R.A. greaterthan 22 h and less then 0.04 h, and a declination greater than +21 deg30 min and less than +27 deg 30 min, covering the Zwicky fields 470 to488, as the second installment of a survey of the region of thePisces-Perseus supercluster. New H I line observations made with theArecibo 305 m telescope detected 275 galaxies of 318 studied. Atabulation of derived galaxian properties is given. The redshiftdistribution shows gross departures from that expected for a sample withsimilar magnitude characteristics but homogeneously located in space.These new data will be incorporated into the overall survey of thethree-dimensional structure in the Pisces-Perseus region.
| Radio emission in isolated and cluster spiral galaxies
In the 2380-MHz continuum radio observations presented for two samplesof spiral galaxies observed with the NAIC Arecibo 305-m telescope, thesamples have been chosen in such a way that they differ markedly in thedensity of surrounding galaxies. One sample includes exclusivelygalaxies from the Karachentseva (1973) Catalog of Isolated Galaxies, theother only galaxies found within one Abell radius from the center ofnearby Abell clusters. The goal is to obtain a comparison of the radioproperties of the galaxies in these two samples, to ascertain whetherenvironmental processes affect significantly their radio emissivity.Above a threshold of five times the rms confusion, 7 percent of thecluster galaxies and 5 percent of the isolated ones are detected. Withthe caution required by the effects of confusion on the single-dishobservations, no significant differences are found in theradio-continuum properties of these two samples.
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