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HYPERLEDA. II. The homogenized HI data
After a compilation of HI data from 611 references and new observationsmade in Nançay, we produce a catalog of homogenized HI data for16781 galaxies. The homogenization is made using the EPIDEMIC methodfrom which all data are progressively converted into the adoptedstandard. The result is a catalog giving: 1) the logarithm of twice themaximum rotation velocity, log 2V_Msin i, converted to thesystem of Mathewson et al. (\cite{Mathewson1996}). This quantity isgiven without correction for inclination; 2) the HI magnitude,m21, (area of the 21-cm line width expressed in magnitude)converted to the flux system of Theureau et al. (\cite{Theureau1998});3) the HI velocity, V_HI, expressed with the optical definition (i.e.,using wavelengths instead frequencies). The typical uncertainties are:0.04 for log 2V_Msin i, 0.25 mag for m21 and 9 kms-1 for V_HI.Full Tables \ref{epidemicw}, \ref{epidemicw2}, \ref{epidemicf},\ref{epidemicf2} and Fig. \ref{profiles} are available in electronicform at http://www.edpsciences.org. Full Tables \ref{references},\ref{cataf}, \ref{newdata} and \ref{notes} are available in electronicform 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/A+A/412/57
| Study of Molecular Clouds and Star Formation in the Region of IC 2118
We carried out a12CO survey of molecular clouds in the regionof the reflection nebula IC 2118. Our observations covered the wholearea of IC 2118 (~ 6 deg2) with a 2'.6 beam at a 4' gridspacing. We identified six molecular clouds. Based on a literaturesearch we found a distance value of 210 pc for the reflection nebula andits associated molecular clouds, indicating that the clouds are probablyinteracting with the Orion--Eridanus Bubble. Using this distance value,we determined the physical properties of the clouds. We also made anobjective prism search for Hα emission stars in the region inorder to find possible solar-type stars born in the clouds, andidentified 46 candidate pre-main-sequence stars. Their spectroscopicfollow-up is in progress. Seven of them have so far proved to be T Tauristars.
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| 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.
| 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.
| Infrared and optical photometry of galaxies in four clusters and of a sample of early-type galaxies
JHKL' multi-aperture infrared photoelectric photometry is presented herefor a sample of galaxies belonging to the Virgo and ABCG 539 clusters.Optical and infrared photometry are also given for members of the Hydracluster and of the southern extension of the Perseus supercluster. Wealso give optical photoelectric photometry of 19 early-type (ellipticaland S0) field galaxies.
| 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.
| 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.
| Groups of galaxies within 80 Mpc. I - Grouping hierarchical method and statistical properties
An all-sky sample of 4143 galaxies comprising all the objects with anapparent diameter D(25) larger than 100 arcsec and with recessionvelocities smaller than 6000 km/s (i.e., closer than 80 Mpc) wasanalyzed using a hierarchical algorithm similar to Tully's (1987)algorithm, in order to classify the galaxies into groups defined asentities having an average luminosity density higher than 8 x 10 exp 9solar luminosity in the B band/Mpc cubed. The hierarchy is built on themass density of the aggregates progressively formed by the method,corrected for the loss of faint galaxies with the distance. In this way,264 groups of at least three members were identified, among which 82have more than five members and are located at distances lower than 40Mpc. It was found that (1) almost all the crossing times are lower thanH0 exp -1, confirming the bound nature of the groups; (2) themedian virial mass to blue luminosity ratio of the groups is 74 solarmass per solar luminosity in the B band; and (3) the M/L ratio increaseswith the group size, indicating the presence of dark matter aroundgalaxies to a distance of 500 kpc.
| Southern extension of the Perseus Supercluster?
In order to investigate in 3D the galaxian density enhancement locatedin the south of the Pisces Perseus Supercluster, a redshift survey isconducted of early-type galaxies with a diameter greater than 1 arcminin a region bounded by 20 h and 6 h, and -20 and 0 deg. Data presentedinclude those for 157 radial velocities which, added to all thepreviously known redshifts in this region, show a galaxy distributionconcentrated around 5000 km/s and the presence of a void of about 25/hMpc. These two characteristics are the same as the ones found by Haynesand Giovanelli (1989), in the northern part of the Pisces PerseusSupercluster, suggesting that it could extend toward the south. Acomparison with the recent data obtained in the same region byPellegrini et al. (1990) is presented.
| Inner ring structures in galaxies as distance indicators. III - Distances to 453 spiral and lenticular galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983ApJS...51..149B&db_key=AST
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