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The H I Line Width/Linear Diameter Relationship as an Independent Test of the Hubble Constant
The relationship between corrected H I line widths and linear diameters(LW/LD) for spiral galaxies is used as an independent check on the valueof the Hubble constant. After calibrating the Tully-Fisher (TF) relationin both the B and I bands, the B-band relation is used for galaxies ofmorphological/luminosity types Sc I, Sc I.2, Sc I.3, Sab, Sb, Sb I-II,and Sb II to derive the LW/LD relation. We find that for this sample thescatter in the LW/LD is smallest with a Hubble constant of 90-95 kms-1 Mpc-1. Lower values of the Hubble constantproduce a separation in the LW/LD relation that is a function ofmorphological type. Since a Hubble constant of 90-95 is significantlylarger than the final Key Project value of 72 km s-1Mpc-1, a comparison of TF, surface brightness fluctuation(SBF), and fundamental plane (FP) is made. This comparison indicatesthat the Key Project TF distances to 21 clusters may be too large. For asample of 11 clusters, the Key Project TF distances provide anunweighted mean Hubble constant of 77 km s-1Mpc-1, while a combination of the FP, SBF, and our TFdistances for the same 11 clusters gives H0=91 kms-1 Mpc-1. A more subtle result in our data is amorphological dichotomy in the Hubble constant. The data suggest that ScI galaxies follow a Hubble constant of 90-95 while Sb galaxies follow aHubble constant closer to 75 km s-1 Mpc-1.Possible explanations for this result are considered, but it is shownthat this Sb/Sc I Hubble flow discrepancy is also present in the VirgoCluster and is consistent with previous investigations that indicatethat some galaxies carry a component of age-related intrinsic redshift.
| Distances to Galaxies from the Correlation between Luminosities and Line Widths. III. Cluster Template and Global Measurement of H0
The correlation between the luminosities and rotation velocities ofgalaxies can be used to estimate distances to late-type galaxies. It isan appropriate moment to reevaluate this method given the great deal ofnew information available. The major improvements described hereinclude: (1) the template relations can now be defined by large,complete samples, (2) the samples are drawn from a wide range ofenvironments, (3) the relations are defined by photometric informationat the B, R, I, and K' bands, (4) the multiband information clarifiesproblems associated with internal reddening, (5) the template zeropoints are defined by 24 galaxies with accurately known distances, and(6) the relations are applied to 12 clusters scattered across the skyand out to velocities of 8000 km s-1. The biggest change fromearlier calibrations are associated with point 5. Roughly a 15% increasein the distance scale has come about with the fivefold increase in thenumber of zero-point calibrators. The overall increase in the distancescale from the luminosity-line width methodology is about 10% afterconsideration of all factors. Modulo an assumed distance to the LargeMagellanic Cloud of 50 kpc and no metallicity corrections to the Cepheidcalibration, the resulting value of the Hubble constant isH0=77+/-8 km s-1 Mpc-1, where the erroris the 95% probable statistical error. Cumulative systematic errorsinternal to this analysis should not exceed 10%. Uncertainties in thedistance scale ladder external to this analysis are estimated at ~10%.If the Cepheid calibration is shifted from the LMC to NGC 4258 with adistance established by observations of circumnuclear masers, thenH0 is larger by 12%.
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| 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.
| Homogeneous Velocity-Distance Data for Peculiar Velocity Analysis. III. The Mark III Catalog of Galaxy Peculiar Velocities
This is the third in a series of papers in which we assemble and analyzea homogeneous catalog of peculiar velocity data. In Papers I and II, wedescribed the Tully-Fisher (TF) redshift-distance samples thatconstitute the bulk of the catalog and our methodology for obtainingmutually consistent TF calibrations for these samples. In this paper, wesupply further technical details of the treatment of the data andpresent a subset of the catalog in tabular form. The full catalog, knownas the Mark III Catalog of Galaxy Peculiar Velocities, is available inaccessible on-line databases, as described herein. The electroniccatalog incorporates not only the TF samples discussed in Papers I andII but also elliptical galaxy Dn- sigma samples originally presentedelsewhere. The relative zero pointing of the elliptical and spiral datasets is discussed here. The basic elements of the Mark III Catalog arethe observables for each object (redshift, magnitude, velocity width,etc.) and inferred distances derived from the TF or Dn- sigma relations.Distances obtained from both the forward and inverse TF relations aretabulated for the spirals. Malmquist bias--corrected distances arecomputed for each catalog object using density fields obtained from theIRAS 1.2 Jy redshift survey. Distances for both individual objects andgroups are provided. A variety of auxiliary data, including distancesand local densities predicted from the IRAS redshift surveyreconstruction method, are tabulated as well. We study the distributionsof TF residuals for three of our samples and conclude that they are wellapproximated as Gaussian. However, for the Mathewson et al. sample wedemonstrate a significant decrease in TF scatter with increasingvelocity width. We test for, but find no evidence of, a correlationbetween TF residuals and galaxy morphology. Finally, we derivetransformations that map the apparent magnitude and velocity width datafor each spiral sample onto a common system. This permits theapplication of analysis methods that assume that a unique TF relationdescribes the entire sample.
| The I band Tully-Fisher relation for cluster galaxies: data presentation.
Observational parameters which can be used for redshift-independentdistance determination using the Tully-Fisher (TF) technique are givenfor \ntot spiral galaxies in the fields of 24 clusters or groups. I bandphotometry for the full sample was either obtained by us or compiledfrom published literature. Rotational velocities are derived either from21 cm spectra or optical emission line long-slit spectra, and convertedto a homogeneous scale. In addition to presenting the data, a discussionof the various sources of error on TF parameters is introduced, and thecriteria for the assignment of membership to each cluster are given.
| Influence of a partial incompleteness of the sample on the determination of the Hubble constant.
This paper presents a study of the Malmquist bias effect in thedetermination of the Hubble constant from the method of "sosies"(look-alike) galaxies. It is shown that a bias appears when a partialincompleteness exists in the sample. A new method, based on the use ofthe completeness curve, is proposed to correct for such a bias. Afterthis correction, the Hubble constant drops of about 20% just because ofthe existence of the partial incompleteness. From the present resultsand on the acceptance of the distance modulus of primary calibrators,the value of the Hubble constant would be: H_0_=~60km/s/Mpc with aninternal statistical error of about 2km/s/Mpc.
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| Recalibration of the H-0.5 magnitudes of spiral galaxies
The H-magnitude aperture data published by the Aaronson et al.collaboration over a 10 year period is collected into a homogeneous dataset of 1731 observations of 665 galaxies. Ninety-six percent of thesegalaxies have isophotal diameters and axial ratios determined by theThird Reference Cataloque of Bright Galaxies (RC3; de Vaucouleurs et al.1991), the most self-consistent set of optical data currently available.The precepts governing the optical data in the RC3 are systematicallydifferent from those of the Second Reference Catalogue (de Vaucouleurs,de Vaucouleurs, & Corwin 1976), which were used by Aaronson et al.for their original analyses of galaxy peculiar motions. This in turnleads to systematic differences in growth curves and fiducialH-magnitudes, prompting the present recalibration of the near-infraredTully-Fisher relationship. New optically normalized H-magnitude growthcurves are defined for galaxies of types SO to Im, from which new valuesof fiducial H-magnitudes, Hg-0.5, are measured forthe 665 galaxies. A series of internal tests show that these fourstandard growth curves are defined to an accuracy of 0.05 mag over theinterval -1.5 less than or equal to log (A/Dg) less than orequal to -0.2. Comparisons with the Aaronson et al. values of diameters,axial ratios, and fiducial H-magnitudes show the expected differences,given the different definitions of these parameters. The values ofHg-0.5 are assigned quality indices: a qualityvalue of 1 indicates an accuracy of less than 0.2 mag, quality 2indicates an accuracy of 0.2-0.35 mag, and quality 3 indicates anaccuracy of more than 0.35 mag. Revised values of corrected H I velocitywidths are also given, based on the new set of axial ratios defiend bythe RC3.
| The Catalog of Southern Ringed Galaxies
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
| A southern sky survey of the peculiar velocities of 1355 spiral galaxies
The paper presents data from photometric and spectroscopic observationsof 1355 southern spiral galaxies and uses them to determine theirdistances and peculiar velocities via the Tully-Fisher (TF) relation.I-band CCD surface photometry was carried out using the 1-m and 3.9-mtelescopes at Siding Spring Observatory. H-alpha rotation curves for 965galaxies and 551 H I profiles are presented. The physical parameters,photometric and velocity data, distances, and peculiar velocities of thegalaxies are presented in tabular form. The mean distance, systemicvelocity, and average peculiar velocity of 24 clusters in the sample aregiven. TF diagrams are presented for each cluster.
| I-band CCD surface photometry of spiral galaxies in 16 nearby clusters
Results of I-band CCD surface photometry for 284 spiral galaxies in 16clusters in the redshift range from 3000 to 11,000 km/s are presented.Various effects on surface photometry are discussed, and the relevantcorrections are outlined.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| Large peculiar velocities in the Hydra-Centaurus supercluster
Distances from the infrared Tully-Fisher relation have been obtainedwith the Parkes radio telescope for six clusters of galaxies in theHydra-Centaurus supercluster. Three of these clusters show significantpositive peculiar velocities of order 500 km/s in a comoving referenceframe in which the observer is at rest with respect to the cosmicmicrowave background radiation. The net peculiar velocity of the samplesuggests that Hydra-Centaurus tends to share the motion of the LocalGroup in this reference frame. The data also fit a model in which twomass concentrations, one at Virgo and one just beyond the centroid ofthe Parkes sample, perturb the Hubble flow.
| Southern Galaxy Catalogue.
Not Available
| The Antlia cluster of galaxies and its environment - The Hydra I-Centaurus supercluster
The small Antlia cluster of galaxies was investigated by measuring manyradial velocities for galaxies from the Lauberts catalog in the Antliaregion. Apart from the Antlia cluster itself, four more small groupswere identified. These five systems form a tiny but not bound Antliamini-supercluster. The mini-supercluster consists of small groups andclusters and of a dispersed component of field galaxies. The five galaxysystems are also part of the large Hydra I-Centaurus supercluster. Thislarge supercluster belongs now to the class of well observed ones. Ithas a chain-like filamentary structure. This supercluster seems to beconnected to the Local Supercluster via two very extended but very loosegroups. The total structure is the triangle-shaped Virgo-HydraI-Centaurus supercluster.
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