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Kinematics of the local universe . XII. 21-cm line measurements of 586 galaxies with the new Nançay receiver
This paper presents 586 new 21-cm neutral hydrogen line measurementscarried out with the FORT receiver of the meridian transit Nançayradiotelescope in the period July 2000-March 2003. This observationalprogramme is part of a larger project aiming at collecting an exhaustiveand magnitude-complete HI extragalactic catalogue for Tully-Fisherapplications. It is associated with the building of the MIGALEspectroscopic archive and database.Tables 2, 3 and HI-profiles and corresponding comments are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/373, or directly atour web site http://klun.obs-nancay.fr
| 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.
| 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.
| Environments of Redshift Survey Compact Groups of Galaxies
Redshift survey compact groups (RSCGs) are tight knots of N >= 3galaxies selected from the CfA2+SSRS2 redshift survey. The selection isbased on physical extent and association in redshift space alone. Wemeasured 300 new redshifts of fainter galaxies within 1 h^-1 Mpc of 14RSCGs to explore the relationship between RSCGs and their environments.Thirteen of 14 RSCGs are embedded in overdense regions of redshiftspace. The systems range from a loose group of five members to an Abellcluster. The remaining group, RSCG 64, appears isolated. RSCGs areisolated and distinct from their surroundings to varying degrees, as arethe Hickson compact groups. Among the 13 embedded RSCGs, three aredistinct from their general environments (RSCG 9, RSCG 11, and RSCG 85).
| 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.
| Stellar populations of cluster E and S0 galaxies
Spectral line index data for a sample of 290 E and S0 galaxies are usedto investigate the stellar populations of these galaxies. 250 of thegalaxies are members of 11 nearby clusters (cz_CMB<11500 km s^-1). Westudy how the stellar populations of the galaxies are related to thevelocity dispersions, the masses of the galaxies, and the clusterenvironment. This is done by establishing relations between theseparameters and the line indices Mg_2, and Hβ_G. Thedifference between the slope of the Mg_2-sigma relation and the slope ofthe -sigma relation indicates that the abundance ratio [Mg/Fe]is 0.3-0.4 dex higher for galaxies with velocity dispersions of 250 kms^-1 compared to galaxies with velocity dispersions of 100 km s^-1. Thisis in agreement with previous estimates by Worthey et al. The index is more strongly correlated with the projected cluster surfacedensity, rho_cluster, than with the galactic mass or the velocitydispersion. Earlier we found that the residuals for the Mg_2-sigmarelation depend on the cluster environment. Here we determine how boththe Mg_2 index and the index depend on the velocitydispersion and rho_cluster. Alternative explanations that could create aspurious environment dependence are discussed. No obvious alternativesare found. The environment dependence of the Mg_2-sigma relation issupported by data from Faber et al. The dependence on the environmentimplies that [Mg/Fe] decreases with increasing density, rho_cluster. Thedecrease in [Mg/Fe] is 0.1 dex over 2.5 dex in rho_cluster. We have alsostudied the extent to which the mass-to-light (M/L) ratios of thegalaxies are determined by the stellar populations. The M/L ratios arestrongly correlated with the indices Mg_2 and Hβ_G, while the index is only weakly correlated with the M/L ratio. Based oncurrent stellar population models, we find that it is not yet possibleto derive unique physical parameters (mean age, mean abundances, meanIMF, and fraction of dark matter) from the observables (line indices,velocity dispersion, mass, M/L ratio).
| The luminosity function of dwarf galaxies in four spiral- rich clusters
We measure luminosity functions in the cores of four spiral-rich, poorclusters of galaxies at median redshift z=0.016. In the red magnituderange -14
| 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 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.
| Spectroscopy for E and S0 galaxies in nine clusters
Central velocity dispersions, Mg_2 line indices and radial velocitiesfor 220 E and S0 galaxies are derived on the basis of intermediateresolution spectroscopy. Galaxies in the following clusters have beenobserved: Abell 194, Abell 539, Abell 3381, Abell 3574, S639, S753,Doradus, HydraI (Abell 1060) and Grm 15. For 151 of the galaxies, thevelocity dispersion has not previously been measured. 134 of the Mg_2determinations are for galaxies with no previous measurement. Thespectra cover either 500 or 1000A, centred on the magnesium triplet at5177A. The observations were obtained with the Boller & Chivensspectrograph at the ESO 1.5-m telescope and with the OPTOPUS, amulti-object fibre-fed B&C spectrograph, at the ESO 3.6-m telescope.The data are part of our ongoing study of the large-scale motions in theUniverse and the physical background for the Fundamental Plane. TheFourier fitting method was used to derive the velocity dispersions andradial velocities. The velocity dispersions have been corrected for theeffect of the size of the aperture. The correction was established onthe basis of velocity dispersion profiles available in the literature. Acomparison with results from Davies et al. shows that the derivedcentral velocity dispersions have an rms error of 0.036 in logsigma.There is no offset relative to the velocity dispersions from Davies etal. The offset relative to data from Lucey & Carter is-0.017+/-0.011 in logsigma, with our velocity dispersions being thesmallest. The velocity dispersions derived from the B&C and theOPTOPUS observations, as well as the velocity dispersions published byDavies et al., Dressler, Lucey & Carter and Lucey et al., can bebrought on a system consistent within 3 per cent. The Mg_2 line indiceshave been corrected for the size of the apertures, transformed to theLick system, and corrected for the effect of the velocity dispersion.From comparison with data from Davies et al. and from Faber, we findthat the rms error of Mg_2 is 0.013. Comparisons of the radialvelocities with data from the literature show that our determinationsare accurate to within ~=35 km s^-1. The accuracies reached for theseobservations are adequate for the study of the large-scale motions inthe Universe and for investigations of the Fundamental Plane.
| Multicolour CCD surface photometry for E and S0 galaxies in 10 clusters
CCD surface photometry for 232 E and S0 galaxies is presented. Thegalaxies are observed in Gunn r and Johnson B, or Gunn r and g. For 48of the galaxies surface photometry in Johnson U is also presented.Aperture magnitudes in Gunn nu are derived for half of the galaxies.Galaxies in the following clusters have been observed: Abell 194, Abell539, Abell 3381, Abell 3574, Abell S639, Abell S753, HydraI (Abell1060), DC2345-28, Doradus and Grm15. The data are part of our ongoingstudy of the large-scale motions in the Universe and the physicalbackground for the fundamental plane. We use a full model fittingtechnique for analysing the CCD images. This gives radial profiles oflocal surface brightness, colour, ellipticity and position angle. Theresiduals relative to the elliptical isophotes are describedquantitatively by Fourier expansions. Effective radius, mean surfacebrightness and total magnitude are derived by fitting a de Vaucouleursr^¼ growth curve. We have derived a characteristic radius r_nsimilar to the diameter D_n introduced by Dressler et al. The derivationof the effective parameters and of r_n takes the seeing into account. Weconfirm the results by Saglia et al. that the effects of the seeing canbe substantial. Seeing-corrected values of the effective parameters andr_n are also presented for 147 E and S0 galaxies in the Coma cluster.Colours, colour gradients and geometrical parameters are derived. Thephotometry is internally consistent within 0.016 mag. Comparison withthe photoelectric aperture photometry from Burstein et al. shows a meanoffset of 0.010 mag with an rms scatter of 0.034 mag. The globalphotometric parameters are compared with data from Faber et al., Luceyet al. and Lucey & Carter. These comparisons imply that the typicalrms errors are as follows - log r_n:+/-0.015 log r_e:+/-0.045m_T:+/-0.09 mag; _e:+/-0.16 mag. The rms error on thecombination log r_e-0.35_e which enters the fundamental planeis +/-0.020. Also, comparisons with data from Saglia et al. arepresented. The accuracy of the absolute photometry, as well as thederived parameters, makes the data suitable for our investigations ofthe fundamental plane and of the large-scale motions in the Universe.
| A Catalog of Stellar Velocity Dispersions. II. 1994 Update
A catalog of central velocity dispersion measurements is presented,current through 1993 September. The catalog includes 2474 measurementsof 1563 galaxies. A standard set of 86 galaxies is defined, consistingof galaxies with at least three reliable, concordant measurements. It issuggested that future studies observe some of these standard galaxies sothat different studies can be normalized to a consistent system. Allmeasurements are reduced to a normalized system using these standards.
| Multicolor surface photometry of early-type galaxies. I.
We have obtained v,g,r and i CCD surface photometry for a sample of 109early-type galaxies. Many of the galaxies covered have no previouslypublished CCD or aperture photometry. Our surface brightness profilestypically extend down to a surface brightness ofμ_r_~24mag/arcsec^2^. Detailed comparisons with previously publishedwork, and internal and external error estimates for all quantities areprovided. The complete surface photometry data set is made available ina computer-readable form.
| General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| 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.
| Distances to five nearby southern galaxy clusters and the absolute motion of the Local Group
Redshifts and central velocity dispersions have been obtained forgalaxies in five nearby southern clusters, and relative distances to theclusters are determined by applying the D-sigma relation to theearly-type galaxies. It is suggested that the large peculiar velocity ofCen45 may be due to its infall toward the more massive Cen30 component.Rich sample clusters such as Cen30 are found to have peculiar velocitieswith respect to the cosmic microwave background.
| Linear clusters of galaxies - A194
New measurements for 160 redshifts and previous measurements for 108other redshifts are presented for galaxies within 5 deg of A194. Thegalaxy distribution in A194 is shown to be inconsistent with aspherically symmetric King model. A mass-to-light ratio is derived usingthe virial theorem which is lower than the mean for the groups in theCfA redshift survey (Huchra and Geller, 1982; Geller, 1984). Anonparametric test for galaxy-cluster alignment and a Chi-squared testare used to search for alignment of galaxy major axes with the axis ofA194. Evidence for neither luminosity segregation nor significantdifferences in the velocity or surface distributions of galaxies as afunction of morphological type is found.
| Candidate Galaxies for Study of the Local Velocity Field and Distance Scale Using Space Telescope - Part Two - the More Difficult Cases
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985AJ.....90.2001S&db_key=AST
| A survey of galaxies in the field of A194
The galaxies in the field of the cluster Abell 194 have been surveyedusing glass plate copies of the Palomar Observatory Sky Survey. Thedistribution in the sky of the diameter-limited galaxy sample has aposition angle of 128 deg and an axial ratio of 0.72. These measurementssuggest that the line of bright galaxies at the cluster center could bea bar of an overall larger filamentary structure, as in a barred spiralgalaxy. Although no statistically significant deviation from random isfound, the galaxy position-angle distribution shows a tendency to lineup along the central bright galaxy line and at right angles to it. Thelatter direction coincides with the position angle determined for theentire sample. For disk galaxies, there is a statistically significantdeviation of the observed axial-ratio distribution from the BdVcomparison sample. An excess of edge-on galaxies and a deficiency ofgalaxies at intermediate axial ratios is found.
| 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.
| Linear clusters of galaxies
Seven linear clusters of galaxies from the catalog of Rood and Sastryhave been studied primarily to determine whether the principal axes ofthe member galaxies exhibit any tendency toward alignment. The majoraxes of galaxies in two of the clusters (Abell 999 and Abell 2197) showa distinct tendency to lie along the cluster major axes. Examination ofall the galaxies in our seven-cluster sample reveals that the major axesof these cluster members tend to lie either along or perpendicular tothe cluster major axis and avoid intermediate position angles. For thissample, there appears to be no correlation between E-galaxy flatteningand cluster shape, a result in contradiction to the recent study byStrom and Strom of ellipticals located in nine clusters of greaterrichness. Significant evidence of mass segregation is found in twoclusters (Abell 179 and Abell 194).
| Low-Dispersion Spectra of Galaxies III. Abell No. 194
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973PASP...85..104P&db_key=AST
| Spectra and Other Characteristics of Interconnected Galaxies and of Galaxies in Groups and in Clusters. III.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1964ApJ...139..269Z&db_key=AST
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