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A Chandra and XMM-Newton study of the wide-angle tail radio galaxy 3C465
We have observed the prototypical wide-angle tail (WAT) radio galaxy3C465 with Chandra and XMM-Newton. X-ray emission is detected from theactive nucleus and the inner radio jet, as well as a small-scale, coolcomponent of thermal emission, a number of the individual galaxies ofthe host cluster (Abell 2634), and the hotter thermal emission from thecluster itself. The X-ray detection of the jet allows us to argue thatsynchrotron emission may be an important mechanism in otherwell-collimated, fast jets, including those of classical double radiosources. The bases of the radio plumes are not detected in the X-ray,which supports the model in which these plumes are physically differentfrom the twin jets of lower-power radio galaxies. The plumes are in factspatially coincident with deficits of X-ray emission on large scales,which argues that they contain little thermal material at the clustertemperature, although the minimum pressures throughout the source arelower than the external pressures estimated from the observed thermalemission. Our observations confirm both spatially and spectrally that acomponent of dense, cool gas with a short cooling time is associatedwith the central galaxy. However, there is no evidence for the kind ofdiscontinuity in external properties that would be required in manymodels of the jet-plume transition in WATs. Although the WAT jet-plumetransition appears likely to be related to the interface between thiscentral cool component and the hotter intracluster medium, the mechanismfor WAT formation remains unclear. We revisit the question of thebending of WAT plumes, and show that the plumes can be bent by plausiblebulk motions of the intracluster medium, or by motion of the host galaxywith respect to the cluster, as long as the plumes are light.
| Color Gradients in Early-Type Galaxies in Abell 2199
We performed B- and R-band surface photometry for E/S0 galaxies in thenearby rich cluster Abell 2199 to investigate their B-R color gradients[d(B-R)/dlogr]. Our aims are to study statistical properties of thecolor gradients and, by comparing them with those in less denseenvironments, to examine environmental dependence of color gradients inelliptical galaxies. We studied the distribution of the B-R colorgradients in the cluster elliptical galaxies and found that the meanvalue of the color gradients is -0.09+/-0.04 mag dex-1, whichcan be converted to a metallicity gradient (dlogZ/dlogr) of -0.3+/-0.1.The gradient seems to be comparable to that expected by a recentmonolithic collapse model. We further studied the relations between theB-R color gradients and global properties of the galaxies. Our datasuggest that for the galaxies brighter than an R-band magnitude of ~15mag, which is roughly equivalent to L* at the distance of the cluster,brighter galaxies tend to have steeper color gradients. In addition, forthe galaxies with effective radii larger than ~3", which nearlycorresponds to L* considering the correlation between galaxy luminosityand effective radius for elliptical galaxies, the galaxies with largereffective radii seem to have steeper color gradients. These trends couldappear if elliptical galaxies formed through the monolithic collapsescenario. On the contrary, it is found based on the published data thatsuch trends are not clearly seen for elliptical galaxies in less denseenvironments, suggesting that elliptical galaxies in sparse environmentsformed by galaxy mergers, although the distribution of the colorgradients is quite similar to that in the rich cluster. In other words,our data and those in the literature suggest that there is anenvironmental dependence in the relationship between color gradient andglobal properties of elliptical galaxies, while the distribution of thevalues of color gradients is nearly independent of galaxy environment.These results do not fully support the view that elliptical galaxies inrich clusters formed through monolithic collapse, while those in sparseenvironments formed through galaxy mergers, because the latterelliptical galaxies are expected to have color gradients shallower onaverage than the former. This apparent conflict may be reconciled bytaking into account star formation and subsequent chemical enrichmentinduced by a galaxy merger, which may allow a merger remnant to acquirea metallicity gradient and thus compensate the dilution of the existingmetallicity gradients in the progenitors by mixture of stars during thegalaxy merger.
| Evolution of Star-forming and Active Galaxies in Nearby Clusters
We have used optical spectroscopy to investigate the active galaxypopulations in a sample of 20 nearby Abell clusters. The targets wereidentified on the basis of 1.4 GHz radio emission, which identifies themas either active galactic nuclei (AGNs) or galaxies forming stars atrates comparable to or greater than that of the Milky Way. The spectrawere used to characterize the galaxies via their emission and absorptionfeatures. The spectroscopy results reveal a significant population ofstar-forming galaxies with large amounts of nuclear dust extinction.This extinction eliminates bluer emission lines such as [O II] from thespectra of these galaxies, meaning their star formation could easily beoverlooked in studies that focus on such features. Around 20% of thecluster star-forming galaxies have spectra of this type. The radialdistributions of active galaxies in clusters show a strong segregationbetween star-forming galaxies and AGNs, with star-forming galaxiesbroadly distributed and AGNs preferentially in the cluster cores. Theradial distribution of the dusty star-forming galaxies is more centrallyconcentrated than the star-forming galaxies in general, which arguesthat they are a consequence of some cluster environmental effect.Furthermore, we note that such galaxies may be identified using their4000 Å break strengths. We find that discrepancies in reportedradio luminosity functions for AGNs are likely the result ofclassification differences. There exists a large population of clustergalaxies whose radio fluxes, far-infrared fluxes, and optical magnitudessuggest their radio emission may be powered by stars yet whose spectralack emission lines. Understanding the nature of these galaxies iscritical to assessing the importance of AGNs in the radio luminosityfunction at low luminosities. We also find that regardless of thispopulation, the crossover point where the radio luminosity function iscomposed equally of star-forming galaxies and AGNs occurs at lowerluminosities in clusters than in the field. This is likely a simpleconsequence of the reduction in star formation in cluster galaxies andthe morphological mix in clusters compared with the field.Based in part on observations obtained with the Apache Point Observatory(APO) 3.5 m telescope, which is owned and operated by the AstrophysicalResearch Consortium.
| 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.
| 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 Radio Galaxy Populations of Nearby Northern Abell Clusters
We report on the use of the NRAO VLA Sky Survey (NVSS) to identify radiogalaxies in 18 nearby Abell clusters. The listings extend from the coresof the clusters out to radii of 3 h-175 Mpc, whichcorresponds to 1.5 Abell radii and approximately 4 orders of magnitudein galaxy density. To create a truly useful catalog, we have collectedoptical spectra for nearly all of the galaxies lacking public velocitymeasurements. Consequently, we are able to discriminate between thoseradio galaxies seen in projection on the cluster and those that are inactuality cluster members. The resulting catalog consists of 329 clusterradio galaxies plus 138 galaxies deemed foreground or backgroundobjects, and new velocity measurements are reported for 273 of theseradio galaxies. The motivation for the catalog is the study of galaxyevolution in the cluster environment. The radio luminosity function is apowerful tool in the identification of active galaxies, as it isdominated by star-forming galaxies at intermediate luminosities andactive galactic nuclei (AGNs) at higher luminosities. The flux limit ofthe NVSS allows us to identify AGNs and star-forming galaxies down tostar formation rates less than 1 Msolar yr-1. Thissensitivity, coupled with the all-sky nature of the NVSS, allows us toproduce a catalog of considerable depth and breadth. In addition tothese data, we report detected infrared fluxes and upper limits obtainedfrom IRAS data. It is hoped that this database will prove useful in anumber of potential studies of the effect of environment on galaxyevolution. Based in part on observations obtained with the Apache PointObservatory 3.5 m telescope, which is owned and operated by theAstrophysical Research Consortium (ARC).
| Structure of the Clusters of Galaxies A 2634, A 1983, and DC 0428-53
The hierarchical and dynamical structure of three clusters of galaxies,A 2634, A 1983, and DC 0428-53, is investigated. Based on their example,we can say that the central cD galaxies play the leading role inclusters, affecting the course of their evolution. Radio and x-raygalaxies are not always part of the substructure. The morphologicalcomposition of various hierarchical subgroups depends on the stage ofevolution. Clusters have a tendency to be oriented in the directiontoward the nearest neighbor.
| Multicolor Photometry of the Galaxies in the Central Region of Abell 2634
An optical photometric observation with theBeijing-Arizona-Taipei-Connecticut multicolor system is carried out forthe central region of the nearby cluster of galaxies Abell 2634. Fromthe 2K×2K CCD images with 14 filters, which cover a range ofwavelength from 3600 to 10000 Å, 5572 sources are detected down toV~20 mag in a field of 56'×56' centered onthis regular cluster of galaxies. As a result, we achieved the spectralenergy distributions (SEDs) of all sources detected. There are 178previously known galaxies included in our observations, 147 of whichhave known radial velocities in the literature. After excluding theforeground and background galaxies, a sample of 124 known members isformed for an investigation of the SED properties. The comparison ofobserved SEDs of the early-type member galaxies with the template SEDsdemonstrates the accuracy and reliability of our photometricmeasurements. Based on the knowledge of SED properties of membergalaxies, we performed the selection of faint galaxies belonging toAbell 2634. It is well shown that the color-color diagrams are powerfulin the star-galaxy separation. As a result, 359 faint galaxies areselected by their color features. The technique of photometric redshiftand color-magnitude correlation for the early-type galaxies are appliedfor these faint galaxies, and a list of 74 faint member galaxies isachieved. On the basis of the newly generated sample of member galaxies,the spatial distribution and color-magnitude relation of the galaxies inthe core region of Abell 2634 are discussed. There exists a tendencythat the color index dispersion of the early-type members is larger forthe outer region, which might reflect some clues about the environmentaleffect on the evolution of galaxies in a cluster.
| Stellar population of ellipticals in different environments: near-infrared spectroscopic observations
Near-infrared spectra of 50 elliptical galaxies in the Pisces, Abell2199 and 2634 clusters, and in the general field, have been obtained.The strength of the CO (2.3-mu m) absorption feature in these galaxiesis used to explore the presence of an intermediate-age population (e.g.asymptotic giant branch stars) in ellipticals in different environments.We find that the strongest evidence for such a population comes fromellipticals in groups of a few members, which we interpret as the resultof recent minor merging of these galaxies with later-type galaxies.Field galaxies from very isolated environments, on the other hand, showno evidence for young or intermediate-age stars as revealed by Hβand CO absorptions, and appear to form a very uniform, old populationwith very little scatter in metallicity and star formation history.
| The peculiar motions of early-type galaxies in two distant regions - II. The spectroscopic data
We present the spectroscopic data for the galaxies studied in the EFARproject, which is designed to measure the properties and peculiarmotions of early-type galaxies in two distant regions. We have obtained1319 spectra of 714 early-type galaxies over 33 observing runs on 10different telescopes. We describe the observations and data reductionsused to measure redshifts, velocity dispersions and the Mgb and Mg_2Lick linestrength indices. Detailed simulations and intercomparison ofthe large number of repeat observations lead to reliable error estimatesfor all quantities. The measurements from different observing runs arecalibrated to a common zero-point or scale before being combined,yielding a total of 706 redshifts, 676 velocity dispersions, 676 Mgblinestrengths and 582 Mg_2 linestrengths. The median estimated errors inthe combined measurements are Delta cz=20 km s^-1, Delta sigma sigma=9.1 per cent, Delta Mgb Mgb=7.2 per cent and Delta Mg_2=0.015 mag.Comparison of our measurements with published data sets shows nosystematic errors in the redshifts or velocity dispersions, and onlysmall zero-point corrections to bring our linestrengths on to thestandard Lick system. We have assigned galaxies to physical clusters byexamining the line-of-sight velocity distributions based on EFAR andZCAT redshifts, together with the projected distributions on the sky. Wederive mean redshifts and velocity dispersions for these clusters, whichwill be used in estimating distances and peculiar velocities and to testfor trends in the galaxy population with cluster mass. The spectroscopicparameters presented here for 706 galaxies combine high-quality data,uniform reduction and measurement procedures, and detailed erroranalysis. They form the largest single set of velocity dispersions andlinestrengths for early-type galaxies published to date.
| 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.
| 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.
| Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.
| The peculiar motions of early-type galaxies in two distant regions. III - The photometric data
We present R-band CCD photometry for 776 galaxies observed in the EFARproject. The photometry is compared with photoelectric data, showingthat a common zero-point good to better than 1 per cent and a precisionof 0.03 mag per zero-point have been achieved. We give the circularlyaveraged surface brightness profiles and the photometric parameters ofthe 762 program galaxies, D(n) diameters, half-luminosity radii, totalmagnitudes, and average effective surface brightnesses. More than 80percent of the profiles have a global S/N ratio larger than 300. Theextrapolation needed to derive total magnitudes is less than 10 percentfor 80 percent of the fits. More than 80 percent of the galaxies havemean effective surface brightness larger than the observed skybrightness. In 90 percent of the profiles the estimate of thecontamination of the sky by the galaxy light is less than 1 percent. Wederive total magnitudes and half-luminosity radii to better than 0.15mag and 25 percent, respectively, for 90 percent of our sample. Incontrast, external comparisons show that data in the literature can bestrongly affected by systematic errors due to large extrapolations,small radial range, sky subtraction errors, seeing effects, and the useof a simple R exp 1/4 fit. The resulting errors can easily amount tomore than 0.5 mag in the total magnitudes and 50 percent in thehalf-luminosity radii.
| Abell 2199 and Abell 2634 revisited
Previous D_n-sigma work found surprisingly large negative peculiarvelocities for Abell 2199 and Abell 2634. In order to assess theseresults independently we have made new spectroscopic and photometricobservations. We report 141 new redshift, velocity dispersion (sigma)and Mg_2 index measurements, and photometry for 79 early-type galaxies.Special attention has been paid to linking the new sigma measurements onto a standard system that minimizes systematic errors. While the Abell2199 sigma measurements are in good agreement with our previouslyreported FLEX values, for Abell 2634 galaxies the new sigmas aresystematically lower. The FLEX measurements for some Abell 2634 galaxiesappear to have been erroneous due to a smearing problem with the CCDdetector. The new photometric data are in excellent agreement withpreviously reported values. We also present a new compilation of datafor 72 early-type Coma cluster galaxies. Assuming that the Coma clusterlies at rest with respect to the cosmic microwave background frame, wederive peculiar velocities of -160+/-380 and -670+/-490 km s^-1 forAbell 2199 and Abell 2634 respectively. We estimate that the likelysystematic errors on these measurements are less than 200kms^-1. Thederived peculiar velocities are considerably less than previousestimates and are not significantly different from zero.
| 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.
| The Peculiar Motions of Early-Type Galaxies in Two Distant Regions. I. Cluster and Galaxy Selection
The EFAR project is a study of 736 candidate elliptical galaxies in 84clusters lying in two regions, toward Hercules-Corona Borealis andPerseus-Pisces-Cetus, at distances cz ~ 6000-15,000 km s^-1^. In thispaper (the first of a series), we present an introduction to the EFARproject and describe in detail the selection of the clusters andgalaxies in our sample. Fundamental data for the galaxies and clustersare given, including accurate new positions for each galaxy andredshifts for each cluster. The galaxy selection functions aredetermined by using diameters measured from Schmidt sky survey imagesfor 2185 galaxies in the cluster fields. Future papers in this serieswill present the spectroscopic and photometric observations of thissample, investigate the properties of the fundamental plane forelliptical galaxies, and determine the large- scale peculiar velocityfields in these two regions of the universe.
| The fundamental plane of early-type galaxies: stellar populations and mass-to-light ratio.
We analyse the residuals to the fundamental plane (FP) of ellipticalgalaxies as a function of stellar-population indicators; these are basedon the line-strength parameter Mg_2_ and on UBVRI broad-band colors, andare partly derived from new observations. The effect of the stellarpopulations accounts for approximately half the observed variation ofthe mass-to-light ratio responsible for the FP tilt. The residual tiltcan be explained by the contribution of two additional effects: thedependence of the rotational support, and possibly that of the spatialstructure, on the luminosity. We conclude to a constancy of thedynamical-to-stellar mass ratio. This probably extends to globularclusters as well, but the dominant factor would be here the luminositydependence of the structure rather than that of the stellar population.This result also implies a constancy of the fraction of dark matter overall the scalelength covered by stellar systems. Our compilation ofinternal stellar kinematics of galaxies is appended.
| Corrections and additions to the third reference catalogue of bright galaxies
List of corrections and additions to the Third Reference Catalogue ofBright Galaxies (RC3) are given. The corrected version of the catalogue(RC3.9b), dated April 1994, is currently available through the nationaldata centers.
| Photoelectric and CCD photometry of E and S0 galaxies
We present BR photoelectric photometry for 352 E and S0 galaxies thatare part of a large survey of the properties and peculiar motions ofgalaxies in distant clusters. Repeat measurements show our internalerrors to be 2-3 percent in B and R and 1-2 percent in B-R. Comparisonsof BR and BVR reductions for 10 galaxies also observed in V show smallsystematic errors due to differences between the spectral energydistributions of stars and galaxies. External comparisons with B-Vcolors in the literature confirm that these colors are good to 1percent. We also describe R-band CCD observations for 95 of the galaxiesand place these on a BR photometric system for photoelectric and CCDphotomerry, with a common zero-point good to better than 1 percent. Wefind the rms precision of both our photoelectric and CCD R magnitudes tobe 2-3 percent for galaxies as faint as R = 15.
| 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
| New distances to and peculiar motions of two Abell clusters - Evidence for spurious motions?
The paper presents redshifts and central velocity dispersions (sigma)from observations with the FLEX-based multiobject system on the WilliamHerschel 4.2-m telescope for early-type galaxies in three rich clusters,Abell 194, Abell 2199, and Abell 2634. In particular, for Abell 2634, acluster distance is derived that gives a highly significant peculiarvelocity of -3400 + or - 600 km/s. It is noted that the IR Tully-Fisherdistance for Abell 2634 spiral galaxies implies only a small peculiarvelocity. It is argued that the effects of tidal stripping in the coreof this cD dominated cluster may have caused a zero-point difference inthe D-sigma relation and hence the large peculiar motion observed herefor Abell 2634 may be spurious.
| The kinematics of Abell clusters
Velocity histograms, galaxy positions, and velocity dispersions arepresented for 69 nearby Abell clusters. The shape of the cumulativedistribution for R = 1 or more clusters does not match the predictionsof standard CDM models for any biasing parameter b. The only modelsconsistent with the median and maximum dispersions of the sample arethose of b about 1.6-2.0 and in which clusters are identified in threedimensions. Velocity dispersions of high-redshift systems appearfundamentally different from those of nearby clusters. The mediandispersion of the subset of 25 cD clusters is similar to that of non-cDsystems. A substantial fraction of the cD galaxies have velocitiessignificantly different from the mean of their parent clusters. Three ofthese have 4 s or more measured redshifts. These last two resultssuggest that the formation of cD galaxies is dominated by the local,rather than global, cluster environment.
| The Asiago Supernova Catalogue
A Catalogue of Supernovae (SNe) is presented which tabulates the maindata relative to all extragalactic SNe discovered up to 1988 December31, and to their parent galaxies. In total 661 SNe are listed of which267 are classified. For an easier consultation, two lists are givenwhere the SNe are ordered chronologically and by Right Ascension,respectively. The overall distribution of classified supernovae over themorphological types of their parent galaxies is also presented in asummary table.
| Bound populations around cD galaxies
Velocity measurements of a complete sample of galaxies within aprojected separation of 200 kpc are presented for the cD clusters A2271,A2589, and A2634. The aim of the measurements was to search for thepresence of a bound population of satellite galaxies that are in theprocess of merging with the cD. It is concluded that the question of thefrequency of bound populations around cD galaxies remains open sincemost clusters have not yet been observed in the detail that is requiredto discover these populations.
| A Checklist of Supernovae in the NGC and IC Galaxies Through 1985
This Checklist of Supernovae in the NGC and IC Galaxies Through 1985 ispresented to assist those interested in undertaking a visual orphotographic search for extragalactic supernovae. Some galaxies appearto have had more than one or two supernovae, and these should bemonitored closely for any new outbursts.
| The evolution of galaxies in clusters. IV - Photometry of 10 low-redshift clusters
Colors and magnitudes, obtained from Palomar 48 inch (1.2 m) Schmidtplates in the J and F bands, and morphological types are presented forgalaxies in the cores of 10 nearby clusters of galaxies. In the typicalcluster, the sample includes all galaxies within a radius of 1.5 Mpc(assuming H(0) = 50 km/s/Mpc) of the cluster center and brighter than J= 17.5.The accuracy of the photometry varies with cluster, but mostmagnitudes are accurate to 0.10 mag, and typical errors in the colorsare of the same order. As expected, the colors of the elliptical and S0galaxies show a narrow dispersion about a mean color which decreaseswith magnitude. However, the colors of the spiral galaxies are notentirely as expected, having a smaller dispersion than would have beenpredicted from their morphological types.
| A revised supernova catalogue
Essential data for 568 supernovae, discovered since 1885 up to 1983, andtheir parent galaxies are presented. This catalogue updates and revisesprevious listings, and some of its information is summarized in tabularand graphical form and briefly discussed. An appendix listing the mainreferences to observations of supernovae outside the optical range isprovided.
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