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|The Tully-Fisher Relation in Coma and Virgo Cluster S0 Galaxies|
We use the Tully-Fisher relation (TFR) to compare the behavior of S0 andlate-type spiral galaxies. We determine circular velocities based onstellar kinematics derived from stellar absorption line spectroscopy for10 S0's in the Coma Cluster and eight S0's in the Virgo Cluster. Wecombine these results with similar measurements of 13 Coma S0 galaxiesobtained previously. We find that there is only a small offset,ΔmH~0.2, in the H-band luminosity at a given circularvelocity, vc~200 km s-1, between S0 and late-typespirals. This result implies a similar total H-band mass-to-light ratio(within an effective radius) among disk galaxies of different Hubbletypes. As the older stellar population in S0's is dimmer, this suggestsa somewhat larger fraction of stellar mass in these S0's than inlate-type spirals. We also find that the relation between (I- andH-band) luminosity and vc for the S0 galaxies is at bestpoorly defined and has a scatter of ~1 mag, significantly larger thanthe TFR for late-type spirals, where the observed I- and H-band scatteris σ~0.3-0.5 mag. This substantial scatter confirms the originalfindings of Dressler & Sandage and is similar to that found in astudy by Neistein and coworkers of 18 nearby S0 galaxies in the fieldwhere σI~0.7 mag, but differs from the small scatterfound by Mathieu and coworkers, σI~0.3 mag, for sixnearby S0's. Our results suggest that differing formation histories canlead to S0's with diverse properties and that S0's are more likely to bethe outcomes of minor mergers or some ``preprocessing'' in groups ofgalaxies falling into clusters, rather than simply late-type spiralsthat have been stripped of their gas but are kinematically preserved. Wesuggest that it is likely that many mechanisms, such as slow encounters,tidal interactions, and gas stripping, may have occurred in thelifetimes of the galaxies and produced the heterogeneous class of S0'sthat are observed today.
|1.65 μm (H-band) surface photometry of galaxies. III. observations of 558 galaxies with the TIRGO 1.5 m telescope|
We present near-infrared H-band (1.65 μm ) surface photometry of 558galaxies in the Coma Supercluster and in the Virgo cluster. This dataset, obtained with the Arcetri NICMOS3 camera ARNICA mounted on theGornergrat Infrared Telescope, is aimed at complementing, withobservations of mostly early-type objects, our NIR survey of spiralgalaxies in these regions, presented in previous papers of this series.Magnitudes at the optical radius, total magnitudes, isophotal radii andlight concentration indices are derived. We confirm the existence of apositive correlation between the near-infrared concentration index andthe galaxy H-band luminosity Based on observations taken at TIRGO(Gornergrat, Switzerland). TIRGO is operated by CAISMI-CNR, Arcetri,Firenze, Italy. Tables 1 and 2 are only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (126.96.36.199) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
|1.65 μm (H-band) surface photometry of galaxies. V. Profile decomposition of 1157 galaxies|
We present near-infrared H-band (1.65 μm) surface brightness profiledecomposition for 1157 galaxies in five nearby clusters of galaxies:Coma, A1367, Virgo, A262 and Cancer, and in the bridge between Coma andA1367 in the ``Great Wall". The optically selected (mpg≤16.0) sample is representative of all Hubble types, from E to Irr+BCD,except dE and of significantly different environments, spanning fromisolated regions to rich clusters of galaxies. We model the surfacebrightness profiles with a de Vaucouleurs r1/4 law (dV), withan exponential disk law (E), or with a combination of the two (B+D).From the fitted quantities we derive the H band effective surfacebrightness (μe) and radius (re) of each component, theasymptotic magnitude HT and the light concentration indexC31. We find that: i) Less than 50% of the Ellipticalgalaxies have pure dV profiles. The majority of E to Sb galaxies is bestrepresented by a B+D profile. All Scd to BCD galaxies have pureexponential profiles. ii) The type of decomposition is a strong functionof the total H band luminosity (mass), independent of the Hubbleclassification: the fraction of pure exponential decompositionsdecreases with increasing luminosity, that of B+D increases withluminosity. Pure dV profiles are absent in the low luminosity rangeLH<1010 L\odot and become dominantabove 1011 L\odot . Based on observations taken atTIRGO, Gornergrat, Switzerland (operated by CAISMI-CNR, Arcetri,Firenze, Italy) and at the Calar Alto Observatory (operated by theMax-Planck-Institut für Astronomie (Heidelberg) jointly with theSpanish National Commission for Astronomy). Table 2 and Figs. 2, 3, 4are available in their entirety only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (188.8.131.52) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
|The Universality of the Fundamental Plane of E and S0 Galaxies: Sample Definition and I-Band Photometric Data|
As part of a project to compare the fundamental plane and Tully-Fisherdistance scales, we present here I-band CCD photometry for 636early-type galaxies in eight clusters and groups of galaxies. These arethe A262, A1367, Coma (A1656), A2634, Cancer and Pegasus Clusters, andthe NGC 383 and NGC 507 Groups. Sample selection, cluster properties,and cluster membership assignment criteria are discussed. We presentphotometric parameters that are used in the fundamental plane relation,the effective radius r_e, and the effective surface brightness mu_e, asderived from a r^1/4 fit to the observed radial photometric profile ofeach galaxy. A comparison with similar data found in the literature forthe Coma Cluster shows that large systematic uncertainties can beintroduced in the measurement of r_e and mu_e by the particular methodused to derive those parameters. However, the particular combination ofthese two parameters that enters in the fundamental plane relation is aquantity that can be measured with high accuracy.
|The distribution of the rotation axes of the disk galaxies in the Coma cluster: statistical samples.|
|The Butcher-Oemler Effect at Low Redshift: Spectroscopy of Five Nearby Clusters of Galaxies|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113..492C&db_key=AST
|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.
|Morphological classification and structural parameters for early-type galaxies in the Coma cluster.|
We present the results of an isophotal shape analysis of three samplesof galaxies in the Coma cluster. Quantitative morphology, together withstructural and photometric parameters, is given for each galaxy. Specialemphasis has been placed on the detailed classification of early-typegalaxies. The three samples are: i) a sample of 97 early-type galaxiesbrighter than m_B_=17.00 falling within one degree from the center ofthe Coma cluster; these galaxies were observed with CCD cameras, mostlyin good to excellent resolution conditions; ii) a magnitude completesample of 107 galaxies of all morphological types down to m_B_=17.00falling in a circular region of 50arcmin diameter, slightly offcenteredto the North-West of the cluster center; the images for this and thenext sample come from digitized photographic plates; iii) a completecomparison sample of 26 galaxies of all morphological types down tom_R_=16.05 (or m_B_=~17.5), also in a region of 50arcmin diameter, butcentered 2.6degrees West of the cluster center. The reliability of ourmorphological classifications and structural parameters of galaxies,down to the adopted magnitude limits, is assessed by comparing theresults on those galaxies for which we had images taken with differentinstrumentation and/or seeing conditions, and by comparing our resultswith similar data from other observers.
|Automated surface photometry for the Coma Cluster galaxies: The catalog|
A homogeneous photometry catalog is presented for 450 galaxies withB25.5 less than or equal to 16 mag located in the 9.8 deg x9.8 deg region centered on the Coma Cluster. The catalog is based onphotographic photometry using an automated surface photometry softwarefor data reduction applied to B-band Schmidt plates. The catalogprovides accurate positions, isophotal and total magnitudes, major andminor axes, and a few other photometric parameters including rudimentarymorphology (early of late type).
|Galaxy Properties at the North Galactic Pole. I. Photometric Properties on Large Spatial Scales|
A two-color study of the galaxies detected on POSS-I in a 289 squaredegree region centered on the North Galactic Pole is presented. We use avariety of mapping techniques to characterize the large-scale spatialdistribution of galaxies. The depth and sample size of this new surveyallows, for the first time, the isolation of large photometricsubsamples of galaxies in high- and low-density environments on thescale of superclusters. Our principal finding is a statisticallysignificant difference between the mean photometric properties of thesesubsamples in the sense that galaxies in the high-density Coma andfilament environments have redder colors and larger concentrationindices than galaxies drawn from low-density interfilament regions.These results are in accord with the known morphology-density relation.Thus, appropriately chosen photometric and morphological parameters, inconcert with a galaxy surface density map, can be used to selectstructures from the projected galaxy distribution which correspond toregions of high density. An illustration of this point is our discoveryof a concentration of blue galaxies identified in our maps near the coreof the Coma cluster. This feature is comprised of early-type galaxieswhich exhibit signs of current or recent star formation. These resultsare predicated on relations between morphological type and photometricparameters derived from APS scans of POSS-I. We therefore discuss theimage calibration procedures used to compile our catalog of physicallysignificant photometric parameters. We demonstrate the morphologicaltype dependence among quantities such as mean color and imageconcentration index, and the lack of such a dependence for mean surfacebrightness.
|Radio-continuum survey of the Coma/A1367 supercluster. IV - 1.4 GHz observations of CGCG galaxies|
1.4 GHz radio-continuum observations of 148 CGCG galaxies in the Comasupercluster region were obtained with the VLA in C array configuration.Comparison with previous measurements at 0.6 GHz leads to an averagespectral index of 0.8. The structures of 29 galaxies in this regiondetermined with high-resolution VLA (A array) observations arepresented.
|Cross identification of 238 galaxies and use of a colour magnitude relation in the coma cluster|
A catalog of 238 galaxies is obtained by the cross identification ofdata from Kent and Gunn (1982), Godwin and Peach (1977) and Godwin etal. (1983). It contains the radial velocities, bvr magnitudes, colorindices, isophotal radii, and other characteristics of individualgalaxies. This leads to the definition of various samples of radialvelocities complete to various limiting magnitudes depending on radius.The use of a color magnitude relation is discussed to define a class of1340 objects likely to belong to the cluster from their photometry only.
|The Coma Cluster - Part One - a Catalogue of Magnitudes Colours Ellipticities and Position Angles for 6724 Galaxies in the Field of the Coma Cluster|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983MNRAS.202..113G&db_key=AST
|The dynamics of rich clusters of galaxies. I - The Coma cluster|
Self-consistent analytical dynamical models are used to study theendpoint of cluster formation, concentrating on the Coma cluster.Particular attention is paid to the effects of anisotropy in thevelocity dispersion and variations in the energy-distribution functionon the cluster structure, the effect on the core structure of a massivecentral object, the dynamical consequences of morphological segregation,cosmological infall and the edge of a cluster, the distribution of darkmatter in a cluster, and the implications of X-ray observations for thedistribution of gravitating material in a cluster. Radial velocity datais displayed, and new and repeated redshifts are reported for a numberof galaxies in the central regions of the cluster. Cluster membership isdetermined and a velocity-dispersion profile is derived. A compositesurface-density profile is derived, and amazing examples are shown ofmodels with virtually identical surface-density profiles but otherwisecompletely different internal dynamics.
|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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