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Structural properties of isolated early-type galaxies. The dependence of scaling relations on environment
Aims.In order to investigate whether gravitational interactions betweengalaxies are able to modify their structural properties, we determinethe Kormendy relation (KR) for a sample of isolated early-type galaxies(ETG) for which we have measured several photometric parameters. Thisrelation is compared with that obtained for a sample of ETG of the ComaCluster, and with that obtained for a sample of perturbed S0 galaxiescontained within high-density environments. Methods: Using very strictphysical isolation criteria we selected a sample of 82 E and S0 galaxiesfrom the CfA catalogue, in the redshift range 5000 km s-1≤ cz < 10 000 km s-1. We obtained the photometricparameters, (r_e, < SB_e>) and total magnitude for 21 galaxies inthe B filter and for 23 in the Gunn r filter. Results: The main resultwe obtained is that the KR is the same for isolated galaxies and forgalaxies in high-density environments or in interaction. In addition wefound evidence that the intrinsic dispersion of the KR depends on themagnitude range within which the galaxies are contained (largerdispersion for larger magnitude range), and not on the degree ofgravitational interaction to which these galaxies are subjected.Tables A.1, A.5, A.6 and Figs. B.2-B.9 are only available in electronicform at http://www.aanda.org
| Kinematics of the Local Universe. XIII. 21-cm line measurements of 452 galaxies with the Nançay radiotelescope, JHK Tully-Fisher relation, and preliminary maps of the peculiar velocity field
Aims.This paper presents 452 new 21-cm neutral hydrogen linemeasurements carried out with the FORT receiver of the meridian transitNançay radiotelescope (NRT) in the period April 2003-March 2005. Methods: This observational programme is part of a larger projectaiming at an exhaustive and magnitude-complete HI extragalacticcatalogue for Tully-Fisher applications (the so-called KLUN project, forKinematics of the Local Universe studies, to end in 2008). The wholeon-line HI archive of the NRT today contains reduced HI-profiles for4500 spiral galaxies of declination δ > -40°(http://klun.obs-nancay.fr). Results: As an example of thisapplication, we used the direct Tully-Fisher relation in three (JHK)bands in deriving distances to a large catalogue of 3126 spiral galaxiesdistributed through the whole sky and sampling the radial velocity rangewell between 0 and 8000 km s-1. Thanks to an iterative methodaccounting for selection bias and smoothing effects, we show a detailedand original map of the velocity field in the Local Universe as apreliminary output.Data Tables [see full text], [see full text], and [see full text]and HI-profiles (Fig. [see full text]) are only available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/465/71
| A Digital Archive of H I 21 Centimeter Line Spectra of Optically Targeted Galaxies
We present a homogeneous compilation of H I spectral parametersextracted from global 21 cm line spectra for some 9000 galaxies in thelocal universe (heliocentric velocity-200
| 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.
| Streaming motions of galaxy clusters within 12 000 km s-1 - III. A standardized catalogue of Fundamental Plane data
We report the construction of a new, standardized all-sky catalogue ofFundamental Plane (FP) data from early-type galaxies in clusters, forpeculiar velocity applications. This catalogue is based on a compilationof spectroscopic and photometric data consisting of data reported inprevious papers of this series, plus data from published sources. Wecompare velocity dispersion and Mg2 line-strength data from27 sources, and determine the corrections that bring all data sets on toa standardized system. For the velocity dispersions, the corrections aretypically at the level of ~0.015dex, corresponding to 5 per cent in theFP-estimated distance. The uncertainties in these corrections, however,are considerably smaller: the new data obtained by our group are closelymatched on to the standard system, with systematic uncertainties at thelevel of ~0.005dex in velocity dispersion (<2 per cent in distance).In this respect our catalogue significantly improves upon previouslypublished FP data sets. For the Mg2 line-strength index,corrections are typically at the level of 0.01mag, but the uncertaintiesin these corrections are only ~0.002mag. A similar procedure is employedto compare photometric data from nine different sources, correcting forthe average colours of early-type galaxies. We focus on the combinationof parameters appearing in the FP,XFP=logRe-0.32<μ>e, whereRe and <μ>e are the effective radius andeffective surface brightness, respectively. For the data sets consideredhere we show that no further corrections are required to XFP,given the typical systematic zero-point uncertainties per data source(0.003-0.006dex, or 0.7-1.4 per cent in distance). Finally, we useredshift data to assign galaxies to clusters in an objective way. Wepresent a master catalogue of FP data for 699 galaxies in 56 clusters,the largest high-quality data set of its kind. These data will be usedin future papers to determine the distances and peculiar velocities ofthese clusters, and thus probe the peculiar velocity field within12000kms-1.
| 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 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.
| 21 CM H1 Line Spectra of Galaxies in Nearby Clusters
A compilation of HI line fluxes, systemic velocities and line widths ispresented for \Ndet detected galaxies, mostly in the vicinities of 30nearby rich clusters out to a redshift of z ~ .04, specifically for usein applications of the Tully-Fisher distance method. New 21 cm HI lineprofiles have been obtained for ~ 500 galaxies in 27 Abell clustersvisible from Arecibo. Upper limits are also presented for \Nnod galaxiesfor which HI emission was not detected. In order to provide ahomogeneous line width determination optimized for Tully-Fisher studies,these new data are supplemented by the reanalysis of previouslypublished spectra obtained both at Arecibo and Green Bank that areavailable in a digital archive. Corrections for instrumental broadening,smoothing, signal-to-noise and profile shape are applied, and anestimate of the error on the width is given. When corrected forturbulent broadening and viewing angle, the corrected velocity widthspresented here will provide the appropriate line width parameter neededto derive distances via the Tully-Fisher relation.
| 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.
| 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.
| A spatial, kinematical, and dynamical analysis of Abell 400
The paper presents a detailed spatial, kinematical, and dynamicalanalysis for the cluster A400, based on a nearly complete redshiftsurvey of bright galaxies within 1 Mpc of the cluster center. Adispersed component with a high fraction of spiral galaxies at avelocity of 8200 km/s, and a background group with a mean velocity of13,400 km/s are identified. It is proposed that the main body of A400 iscomposed of at least two individual subclusters. If subclustering isignored, the derived dispersion of the 88 galaxies with measuredvelocities within 4000 km/s of the bright dumbbell galaxy near thecluster center is 702 km/s. When kinematic information is used to splitA400 into likely subclusters, the velocity dispersions of the individualunits which make up this cluster are on the order of 200-300 km/s. IfA400 is considered a single entity, the inferred blue mass-to-lightratio is 1210 solar masses/solar luminosities. It is argued that A400 isan example of a presently occurring merger, and that the individualcomponents of the dumbbell galaxy were once individual D galaxies withinthe premerger subclusters.
| 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 catalog of morphological types in 55 rich clusters of galaxies
Data are presented from a study of 55 rich clusters of galaxies. Thedata include positions, morphological types, estimated total magnitudes,bulge sizes, and ellipticities for about 6000 galaxies, as determinedfrom high scale photographic plates. Data reduction procedures aredescribed, and a brief analysis of cluster richness, which indicatesthat Abell richness classes are only rough indicators of total clustermembership, is included.
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