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|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.
|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.
|Kinematic Evidence of Minor Mergers in Normal SA Galaxies: NGC 3626, NGC 3900, NGC 4772, and NGC 5854|
BVRI and Hα imaging and long-slit optical spectroscopic data arepresented for four morphologically normal and relatively isolated Sagalaxies, NGC 3626, NGC 3900, NGC 4772, and NGC 5854. VLA H I synthesisimaging is presented for the first three objects. In all four galaxies,evidence of kinematic decoupling of ionized gas components is found inthe long-slit spectroscopic data; the degree and circumstances of thedistinct kinematics vary from complete counterrotation of all of the gasfrom all of the stars (NGC 3626) to nuclear gas disks decoupled from thestars (NGC 5854) to anomalous velocity central gas components (NGC 3900and NGC 4772). In the three objects mapped in H I, the neutral gasextends far beyond the optical radius, RHI/R25>=2. In general, the H I surface density isvery low, and the outer H I is patchy and asymmetric (NGC 3900) or foundin a distinct ring, exterior to the optical edge (NGC 3626 and NGC4772). While the overall H I velocity fields are dominated by circularmotions, strong warps are suggested in the outer regions by bending ofthe minor axis isovelocity contours (NGC 3900) and/or systematic shiftsin position angle between inner and outer rings (NGC 3626 and NGC 4772).In the interior, coincidence is found between the Hα and H I inrings, sometimes partial and crisscrossed by dust lanes. Optical imagingis also presented for NGC 4138 previously reported by Jore et al. toshow counterrotating stellar components. The multiwavelength evidence isinterpreted in terms of the kinematic ``memory'' of past minor mergersin objects that otherwise exhibit no morphological signs of interaction.
|H I observations of emission-line galaxies|
We present single-dish Lovell telescope H i observations of a sample of67 emission-line and UV-excess galaxies, of which 52 are taken from theUniversity of Michigan (UM) catalogue. In addition, H i observations of24 gas-rich irregular galaxies are presented. We find that emission-linegalaxies are H i-rich with a median H i mass to blue luminosity ratioMHI/LB of ~ 0.45 Msun/Lsun.Within the UM galaxy sample the MHI/LB ratio tendsto increase with decreasing luminosity. Finally, it is found that themost H i-rich UM galaxies are the most metal deficient, implying thatthese objects are less evolved.
|A Complete Redshift Survey to the Zwicky Catalog Limit in a 2^h X 15 deg Region around 3C 273|
We compile 1113 redshifts (648 new measurements, 465 from theliterature) for Zwicky catalog galaxies in the region (-3.5d <= delta<= 8.5d, 11h5 <= alpha <= 13h5). We include redshifts for 114component objects in 78 Zwicky catalog multiplets. The redshift surveyin this region is 99.5% complete to the Zwicky catalog limit, m_Zw =15.7. It is 99.9% complete to m_Zw = 15.5, the CfA Redshift Survey(CfA2) magnitude limit. The survey region is adjacent to the northernportion of CfA2, overlaps the northernmost slice of the Las CampanasRedshift Survey, includes the southern extent of the Virgo Cluster, andis roughly centered on the QSO 3C 273. As in other portions of theZwicky catalog, bright and faint galaxies trace the same large-scalestructure.
|Catalogue of HI maps of galaxies. I.|
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 188.8.131.52 orhttp://cdsweb.u-strasbg.fr/Abstract.html
|A Minnesota Automated Plate Scanner Catalog of Galaxies behind the Virgo Cluster and toward Its Antipode|
We present a catalog of 1268 galaxies, essentially complete to B <=17.0, found by scanning glass copies of several fields of the originalPalomar Sky Survey using the Minnesota Automated Plate Scanner in itsisodensitometric mode (as opposed to the threshold densitometric modeused in the APS Catalog of the POSS I). In addition to the differentscanning mode, we have employed a different star-galaxy separationmethod and have visually inspected POSS prints to verify that each imageremaining in the catalog is nonstellar. The scanned fields aredistributed generally in two areas, one around the outskirts of theVirgo Cluster, the other toward the antipode of the cluster (but stillin the northern celestial hemisphere). The catalog gives the position ofthe center of each galaxy; estimates of the blue and red magnitudeswithin the outermost threshold crossing and of the blue magnitudeextrapolated to zero surface brightness; and the blue and red diametersof four ellipses fitted to the four threshold crossings (approximately23.8,23.6,23.2, and 22.7 mag arcsec 2 in blue, and 22.5,22.4,21.5, and21.2 mag arcsec^-2^ in red), and the ellipticities of those fourellipses. The catalog has served as a base from which to draw targetsfor a Tully-Fisher study of the Virgocentric infall velocity of theLocal Group.
|The UV properties of normal galaxies. III. Standard luminosity profiles and total magnitudes.|
In the previous papers of this series we collected and reduced to thesame system all the available photometric data obtained in theultraviolet (UV) range for normal (i.e. non active) galaxies. Here weuse these data to derive standard UV luminosity profiles for threemorphological bins (E/S0; Sa/Sb; Sc/Sd) and extrapolated totalmagnitudes for almost 400 galaxies. We find that: 1) the UV growthcurves are well matched by the B-band revised standard luminosityprofiles, once a proper shift in the effective radius is applied, and 2)the UV light in early-type galaxies is more centrally concentrated thanthe visible light.
|The UV properties of normal galaxies. II. The ``non-IUE'' data.|
In the last decade several satellite and balloon borne experiments havecollected a large number of ultraviolet fluxes of normal galaxiesmeasured through apertures of various sizes and shapes. We havehomogenized this data set by deriving scale corrections with respect toIUE. In a forthcoming paper these data will be used to derive standardluminosity profiles and total magnitudes.
|The spatial distribution of supernovae in paired and interacting galaxies|
In order to investigate the location of supernovae (SNe) in paired andinteracting galaxies, the 54 supernovae discovered up to May 1993 in 14Isolated Pairs of Galaxies and the 32 Interacting Systems were taken asa sample and studied. The whole sample of SNe, as well as a subsampleformed of type II, and Ib SNe, whose progenitors are young massivestars, do not appear in any one particluar direction with respect to thecompanion. On paired and interacting galaxies, the radial distributionof type Ib and II SNe peaks more toward the galaxy centers than it doesin isolated galaxies, indicating an enhanced Star Formation Rate (SFR)around the nuclei and in the inner disks. The distribution of SNIaappear similar in both samples, confirming that their progenitors arenot the same as those of SNII and IB. The SN rates are related to galaxyluminosity and, as expected, the discovery of SNe is twice more frequentin the brighter galaxy of the pair than in fainter ones. We did not findany relation between the locations of SNe in parent galaxies, the totalStar Formation activity and the kinematics of paired and interactinggalaxies.
|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.
|A near-infrared imaging survey of interacting galaxies - The small angular-size ARP systems|
Near-IR images of a large sample of interacting galaxies selected fromthe Atlas of Peculiar Galaxies by Arp (1966) have been obtained.Approximately 180 systems have been imaged in at least two, and usuallythree of the standard JHK bands. The survey and the observing and datareduction procedures, are described, and contour plots and aperturephotometry are presented. Future papers will analyze the imaging data bygroupings based on interaction type, stage, and progenitors. The goalsof the analysis are to explore the relationships between galaxyinteractions, activity, and morphology by studying the structure of thenear-IR luminosity distribution, where extinction effects are muchreduced relative to the optical and the major stellar mass component ofgalaxies dominates the observed light.
|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.
|H I observations in the Virgo cluster area. III - All 'member' spirals|
H I observations of 141 spiral galaxies in and around the Virgo Clusterare reported, with major-axis mapping for 65 of them. Heliocentricvelocities, profile widths, and H I fluxes are given for all detectedgalaxies. Spin orientations are given for mapped galaxies and H Idiameters for those sufficiently resolved by the 3.2 arcmin beam. Mappedgalaxy spectra are shown as contour plates of position versus velocity;central beam spectra are shown for the remainder. The distributions ofspin orientations are briefly analyzed and shown to be essentiallyrandom. The distributions of H I luminosity are presented along withindicative dynamical mass for the spirals and a synthesized H Idistribution for the cluster as a whole.
|The far-infrared properties of optically selected emission-line galaxies|
A high-sensitivity sample of IRAS-detected emission-line galaxies (ELGs)is used to investigate the FIR properties of these galaxies and therelative selection biases of the UM Curtis Schmidt and IRAS surveys.Color-color diagrams indicate that the FIR emission from the UM ELGs isdue primarily to warm dust heated directly by the active star-formingregions that are responsible for the strong optical emission lines. TheFIR luminosity of the UM ELGs is found to correlate with both H-beta andblue luminosities, suggesting that the current star-formation rate inthese objects is more closely coupled to the past star-formation historythan is generally acknowledged.
|Ultraviolet observations and star-formation rate in galaxies|
The present 149 galaxies, essentially of spiral and irregular types wereobserved at about 2000 A in a survey using a balloon-borne imagingtelescope. Total ultraviolet fluxes in an about 125-A wide bandpass havebeen obtained by comparison with field stars. On average, the m(2000)-Bcolor gets redder from late to early morphological types. For a giventype, this color exhibits a large scatter which increases from late toearly types. As expected, the galaxies show a relation between them(2000)-B and B-V colors. After a correction for dust extinction basedon the neutral hydrogen content of each galaxy, the observed fluxes areused to obtain quantitative estimates of the current star formation rate(SFR). A good correlation is found between the SFR and the total gascontent. A weak correlation observed between the SFR per unit area andthe average gas surface density might be compatible with the existenceof a power-law relation of exponent 1, between birthrate and gasdensity. The SFR per unit gas mass shows both a significant dispersionand a decrease toward later types. Implications in terms of starformation history are discussed.
|The orbits of H I-deficient spiral galaxies in the Virgo cluster|
A sample of 107 galaxies in the Virgo area has been used to investigatethe orbits of H I-deficient spiral galaxies and the velocity-distancerelation in Virgo. The analysis of the orbits of H I-deficient spiralsindicates that they are very likely to be on radial orbits which carrythem into the intracluster medium of the Virgo core. It is suggestedthat the process of H I-removal occurs in the Virgo core. A new versionof the Tully-Fisher relation in the B-band with probable accuracy of0.35 mag is used to resolve the cluster in depth. Galaxies with low andhigh velocities are found on the near side of the cluster as well as onthe far side. Mass-age infall models with Lambda = 0 have been comparedwith the data.
|The structure of the Virgo cluster of galaxies|
A new detailed analysis of galaxies in the Virgo area shows that theconventional Virgo cluster comprises two different clouds of galaxies:the Virgo cluster I and the Southern cloud II by the definition proposedhere. Excluding the galaxies in the Southern cloud II, the Virgo clusterI centered at 12 h 27.6 m, +13 deg 07 arcmin (1950), has a mean radialvelocity of 980 + or - 60 km/s and there is no significant velocitydifference between elliptical-lenticular and spiral-irregular galaxiesin the Virgo cluster I. The Southern cloud II is centered at about 12 h25 m, +7 deg 30 arcmin (1950) and all types of galaxies in the cloud arediffusely distributed, while elliptical galaxies in the Virgo cluster Iare concentrated to the center. The mean radial velocity within a radiusof 3.5 deg of the Southern cloud II is +1240 + or - 80 km/s, which issignificantly higher than the mean velocity of the Virgo cluster I.
|The nuclear activity of interacting galaxies|
A search for active galactic nuclei among interacting galaxies isreported. A sample of 167 systems of interacting and asymmetric galaxieswas observed spectrophotometrically in the spectral range 4700-7100 A.The results are compared with a sample of isolated galaxies. It is foundthat (1) there are no Seyfert nuclei in elliptical or dwarf irregulargalaxies of the sample; (2) there is an excess of Seyfert nuclei amonginteracting spirals, but it is only at the 90 percent confidence level;(3) this excess becomes statistically significant (98 percent) when onlystrongly interacting spirals are included (four new Seyfert nuclei arepresented); (4) in the subgroup of galaxies with extreme tidaldistortions, no Seyfert nuclei were found.
|Evolution of spiral galaxies in the Virgo Cluster. I - Statistical analysis of H I deficiency and colors|
A compilation of H I data and available UBV, far-UV (2421-angstrom) andH-alpha photometry is presented for 107 spiral and irregular galaxies(SO/a-Im) in the Virgo Cluster, to be compared with a reference sampleof 405 'field' galaxies. Previous findings about the H I deficiency ofVirgo Cluster spirals are confirmed. H I deficient spirals are locatedin subgroups inside Virgo I, in association with the hot gaseousintergalactic medium. (Virgo X is not H I deficient.) Early-type spiralsare more likely to be H I deficient than late-type ones and thedeficiency closely correlates with the colors through this type effect.The H-alpha + N II forbidden-line equivalent widths correlate well withthe H I contents for the Virgo Cluster spirals as well as the referencesample.
|Infall of galaxies into the Virgo cluster and some cosmological constraints|
The observed infall of galaxies in the Virgo Southern Extension towardthe Virgo Cluster is characterized by a family of mass models satisfyingthe requirement of an explanation of the Milky Way's motion with respectto the Virgo Cluster, in order to furnish constraints of cosmologicalinterest. If the age of the universe is 10-15 Gyr, there is a roughcoincidence of the mass required to explain the infall pattern ofgalaxies near the cluster, the mass needed to account for the motion ofthe Milky Way, and the mass implied for the central cluster by thevirial theorem, in which case most of the supercluster's mass mustreside in the Virgo Cluster. With the mass-age models and a census ofthe distribution of galaxies near the Virgo Cluster, it is possible toestimate the near-future accretion rate of galaxies into the centralcluster.
|H I line studies of galaxies. III - Distance moduli of 822 disk galaxies|
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
|Double galaxies - Redshift measurements, error analysis, and mean mass/luminosity ratio|
New radial velocities for 44 double galaxy systems are presented. Theratio k between the internal and external errors in the redshift data isestimated by comparing data from catalog galaxies with a sample fromWhite et al. (1983). This ratio is found to increase from 1.0 to 2.1from galaxies with strong emission lines to absorption-line objects. Thedisparity between the absolute and internal errors diminishes for theredshift differentials of pair components, because the individual errorsin the redshifts measured for the members of a given pair are observedto be positively correlated. The average value of k for the whole sampleis estimated by considering the values of the first four moments of themass/luminosity ratio as functions of k. The absolute error in theredshift differential is 1.4 times the internal error, bringing the meanratio of orbital mass to luminosity for 490 pairs into good agreementwith the values determined from the differential rotation of galaxies.
|Double galaxy investigations. I - Observations|
Redshift information from 240 A/mm spectrograms is presented for 370double arcsec galaxy systems from the Karachentsev (1972) catalog,including all pairs in that catalog with separation less than 80 arcsec.An extensive error discussion utilizing internal and external (21 cm)comparisons provides calibration of systematic error and determines theuncertainty for a typical high weight optical redshift to be plus orminus 65 km/sec. Internal differential redshifts within single spectrausing common lines achieve accuracies of 18-30 km/sec, depending uponseparation, and are available for about 200 pairs. Extensive informationon emission and other properties is also provided.
|A radio continuum survey at 1.4 GHz of the galaxies in the Virgo region|
Radio continuum observations made with the Westerbork Synthesis RadioTelescope at 1.4 GHz are presented for 274 galaxies in the Virgo Clusterregion. The observations are partly full syntheses and partly east-weststrip distributions. For the 55 detected galaxies the emission isseparated into central and extended components. A brief summary of theanalysis is also given.
|Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST
|Binary galaxie. I. A well-defined statistical sample.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJ...208...20T&db_key=AST
|Atlas of Peculiar Galaxies|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966ApJS...14....1A&db_key=AST
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