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The ESO nearby Abell cluster survey. VIII. Morphological and spectral classification of galaxies
We determine the morphological types of 2295 galaxies from the ESONearby Abell Cluster Survey (ENACS) from CCD images obtained with theDutch telescope on La Silla. A comparison with morphological types fromthe literature for 450 of our galaxies shows that the reliability of ourclassification is quite comparable to that of other classifiers. Werecalibrate the ENACS spectral classification with the new morphologicaltypes, and find that early- and late-type galaxies can be distinguishedfrom their spectra with 83% reliability. Ellipticals and S0 galaxies canhardly be distinguished on the basis of their spectra, but late spiralscan be classified from the spectrum alone with more than 70%reliability. We derive pseudo-colors and linestrengths from the ENACSspectra for the galaxies of different morphological types. We considerthe bright (MR ≤ -20) and faint (MR > -20)subsets of the galaxies without emission lines (non-ELG) separately. Wefind a strong and significant correlation between the average color andthe average strength of the metal absorption lines. The averagemetallicity decreases and the average color gets bluer towards laterHubble type. Also, the faint galaxies in each morphological class arebluer and less metal-rich than their brighter counterparts, whichextends the well-established color-magnitude relation of early-typegalaxies to (late) spirals. In view of these very strong global trends,the colors and metallicities of faint S0 galaxies and bright earlyspirals are remarkably similar. The bright early spirals may, onaverage, have somewhat stronger Hδ absorption than the othergalaxies, which could be due to recent starformation. The galaxies withemission lines (ELG) have a bluer spectral continuum than the non-ELG,and the amount of blueing hardly depends on morphological type. Thefraction of ELG depends strongly on morphological type (varying from4±1% for ellipticals to 59±4% for late spirals), but foreach of the morphological types it varies very little with projecteddistance from the cluster center.
| The Seyfert Population in the Local Universe
The magnitude-limited catalog of the Southern Sky Redshift Survey(SSRS2) is used to characterize the properties of galaxies hostingactive galactic nuclei (AGNs). Using emission-line ratios, we identify atotal of 162 (3%) Seyfert galaxies out of the parent sample with 5399galaxies. The sample contains 121 Seyfert 2 galaxies and 41 Seyfert 1galaxies. The SSRS2 Seyfert galaxies are predominantly in spirals oftypes Sb and earlier or in galaxies with perturbed appearance as theresult of strong interactions or mergers. Seyfert galaxies in thissample are twice as common in barred hosts as the non-Seyfert galaxies.By assigning galaxies to groups using a percolation algorithm, we findthat the Seyfert galaxies in the SSRS2 are more likely to be found inbinary systems when compared with galaxies in the SSRS2 parent sample.However, there is no statistically significant difference between theSeyfert and SSRS2 parent sample when systems with more than two galaxiesare considered. The analysis of the present sample suggests that thereis a stronger correlation between the presence of the AGN phenomenonwith internal properties of galaxies (morphology, presence of bar,luminosity) than with environmental effects (local galaxy density, groupvelocity dispersion, nearest neighbor distance).Partly based on observations at European Southern Observatory (ESO),under the ESO-ON agreement to operate the 1.52 m telescope.
| Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| Properties of Very Luminous Galaxies
Recent analysis of the data from the Southern Sky Redshift Surveyextension (SSRS2) based on cell counts and the two-point correlationfunction has shown that very luminous galaxies are much more stronglyclustered than fainter galaxies. In fact, the amplitude of thecorrelation function of very luminous galaxies (L > L^*)asymptotically approaches that of R >= 0 clusters. In this paper weinvestigate the properties of the most luminous galaxies, with blueabsolute magnitudes M_B <= -21. We find that (1) the population mixis comparable to that in other ranges of absolute magnitude; (2) only asmall fraction are located in bona fide clusters; (3) the brightgalaxy-cluster cross-correlation function is significantly higher onlarge scales than that measured for fainter galaxies; (4) thecorrelation length of galaxies brighter than M_B ~ -20.0, expressed as afunction of the mean interparticle distance, appears to follow theuniversal dimensionless correlation function found for clusters andradio galaxies; (5) a large fraction of the bright galaxies are ininteracting pairs, while others show evidence for tidal distortions andsome appear to be surrounded by faint satellite galaxies. We concludethat very luminous optical galaxies differ from the normal population ofgalaxies in both clustering and other respects. We speculate that thispopulation is a highly biased tracer of mass, being associated with darkhalos with masses more comparable to clusters than to typical loosegroups.
| 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
| The ESO Nearby Abell Cluster Survey. V. The catalogue: Contents and instructions for use
We present the catalogue resulting from the ESO Nearby Abell ClusterSurvey (the ENACS), which contains redshifts and magnitudes for 5634galaxies in the directions of 107 rich, nearby southern Abell clustercandidates. We describe the contents of the catalogue and discuss theresults of a comparison between the ENACS catalogue and the COSMOSGalaxy Catalogue. When cross-correlating the two catalogues we findthat, at least in the areas of the ENACS clusters, the completeness ofthe COSMOS catalogue is somewhat lower than was estimated previously forthe carefully analyzed and well-calibrated part of the COSMOS catalogueknown as the Edinburgh-Durham Southern Galaxy Survey (EDSGC). The galaxypositions in the COSMOS and ENACS catalogues are found to be on the samesystem to within about one arcsecond. For the clusters for which thephotometry in the ENACS and COSMOS catalogues is based on the samesurvey plates, the two magnitude scales agree very well. We confirm thatthe photometric calibration in the EDSGC subset of the COSMOS catalogueis of higher quality than in the EDSGC complement. The ENACS galaxysamples are unbiased subsets of the COSMOS catalogue as far as theprojected galaxy distribution is concerned, except in only a few cases.We summarize how the ENACS galaxy samples are subsets of the COSMOScatalogues in the ENACS apertures, with respect to magnitude. For theENACS catalogue as a whole, we describe the apparent incompleteness atfaint magnitudes and towards higher redshifts. Finally, we provide somedetailed information about the ENACS catalogue that is essential for itsproper statistical use and we summarize some facts that must beremembered when selecting subsets of galaxies from it. Based onobservations collected at the European Southern Observatory (La Silla,Chile).
| 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.
| Properties of nearby clusters of galaxies. II. A 151, A 637, A 646, A 649, A 655, A 1132, A 1314, A 1377, A 1570, A 1589.
We present F band photometry, from digitized 48-inch Palomar plates, of1167 galaxies brighter than m_3_+3 in 10 Abell clusters. For eachgalaxy, absolute coordinates, magnitude, size, ellipticity endorientation are given. For each cluster we provide finding charts andcontour maps of the galaxy surface density.
| The morphological catalogue of galaxies equatorial survey
We present 865 redshifts of galaxies located in the equatorial stripdelta between -17.5 deg and -2.5 deg in the right ascension rangebetween 20 h and 5 h. Redshifts have been obtained for the completesample of all 833 galaxies in the Morphological Catalog of Galaxies withmagnitudes brighter than m = 14.5 (corresponding approximately tom(Zwicky) = 15.0). This sample also includes three galaxies from othersources with more reliable magnitudes, satisfying this limit, and 29fainter galaxies, usually companions of the galaxies in the magnitudelimited sample. Our maps of a very large volume of nearby spacedemonstrate a variety of coherent large scale structures which includelarge voids, 20-50/h Mpc in diameter and large walls at least 70/h Mpcacross.
| Observational data for the kinematics of the local universe. I - Radial velocity measurements
The study of the local velocity field requires the use of a very largesample to describe as accurately as possible some prominent features ofthe local kinematics. The problem of collecting a large sample is mademore difficult because of the Malmquist bias which plagues distancedeterminations. The present program aims at determining bias-freedistances for a complete sample in order to study the local velocityfield. The present paper gives 303 preliminary optical and radioredshifts measured for this program at ESO, OHP and NancayObservatories.
| The cluster of galaxies Abell 151
We use a sample of 65 redshifts to study the kinematics and dynamics ofthe cluster Abell 151. Data on individual galaxies are presented, andthe accuracy of the determined velocities are discussed as well as someproperties of the cluster. The velocity data reveal a foreground groupand a background population at the same redshifts as the closelyprojected cluster A 166.
| A 20 CM VLA survey of Abell clusters of galaxies. I - Distance class of not greater than 3 clusters
Nearby Abell clusters of distance class of not greater than 3 arestudied based on 20-cm VLA observations, Westerbork Synthesis RadioTelescope results, and Einstein Observatory X-ray data. No significantcorrelation is found between the 20-cm radio power and X-ray luminosity,and no evidence is found that regular-type clusters are statisticallymore likely to be radio loud than irregular-type clusters. A weakcorrelation is noted between X-ray-cooling mass-accretion rates andradio powers for central dominant galaxies in cooling-flow clusters,suggesting that either cooling accretion directly fuels the centralengine and/or cooling flows strongly interact with the radio plasma.
| 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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