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The scaling relation of early-type galaxies in clusters. II. Spectroscopic data for galaxies in eight nearby clusters
Aims.We present low and intermediate resolution spectroscopic datacollected for 152 early type galaxies in 8 nearby clusters with z ≤0.10. Methods: .We use low resolution data to produce the redshiftand the K-correction for each galaxy, as well as to give their overallspectral energy distribution and some spectral indicators, including the4000 Å break, the Mg2 strength and the NaD equivalent width. Wehave also obtained higher resolution data for early type galaxies inthree of the clusters, to determine their central velocity dispersion. Results: .The effect of the resolution on the measured parametersis discussed. Conclusions: .A new accurate systemic redshift andvelocity dispersion is presented for four of the surveyed clusters, A98,A3125, A3330, and DC2103-39. We have found that the K-correction valuesfor E/S0 bright galaxies in the given nearby clusters are very similar.We also find that the distribution of the line indicators significantlydiffers from cluster to cluster.
| The scaling relations of early-type galaxies in clusters. I. Surface photometry in seven nearby clusters
This is the first paper of a series investigating the scaling relationsof early-type galaxies in clusters. Here we illustrate the multi-bandimagery and the image reduction and calibration procedures relative tothe whole sample of 22 clusters at 0.05 <~ z <~ 0.25. We alsopresent detailed surface photometry of 312 early-type galaxies in 7clusters in the first redshift bin, z ≈0.025-0.075. We give for eachgalaxy the complete set of luminosity and geometrical profiles, and anumber of global, photometric and morphological parameters. They havebeen evaluated taking into account the effects of seeing. Internalconsistency checks and comparisons with data in the literature confirmthe quality of our analysis. These data, together with the spectroscopicones presented in the second paper of the series, will provide the localcalibration of the scaling relations. Tables 6, 7a-7g, the colour printsof Figs. 12a-12g AND Figs. 13a-13g are only available in electronic format http://www.edpsciences.com. The complete set of profiles is availableupon request from the authors. Tables 7a-7g are also available inelectronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.188.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/387/26
| Kinematics of the Hercules supercluster
The Hercules supercluster consists of the Abell clusters A2147, A2151,and A2152. Previous studies of the kinematics have been confounded bythe difficulty of correctly assigning galaxies to the individualclusters, which are not well separated. Our study has a total of 468available velocities for galaxies in the region, 175 of them new. Thereare 414 galaxies in the supercluster, about three times the number usedin the previous supercluster study. We verify the existence of the threeindividual clusters and compute their individual dynamical parameters.We investigate several techniques for assigning galaxy membership toclusters in this crowded field. We use the KMM mixture-modelingalgorithm to separate the galaxies into clusters; we find that A2152 hasa higher mean velocity than previous studies have reported. A2147 andA2152 also have lower velocity dispersions: 821 and 715 km/s,respectively. The assignment of galaxies to either A2152 or A2147requires velocity and position information. We study the kinematics ofthe supercluster using the two-body formalism of Beers et al. (1982) andconclude that A2147 and A2151 are probably bound to each other and thatthe supercluster as a whole may also be bound. The mass of thesupercluster, if bound, is (7.6 +/- 2.0) 10 exp 15/h M(solar); with thesupercluster luminosity, (1.4 +/- 0.2) 10 exp 13/sq h L(solar), thisyields 0.34 +/- 0.1.
| 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.
| The complex structure of Abell 2151 (Hercules)
We analyzed the space distribution of 117 galaxies in an area of 0.9 degradius centered on NGC 6045 in the Hercules cluster in the velocityrange 9000 to 14,000 km/s. By taking advantage of 74 morphologies basedon CCD images, we succeed in isolating a cluster of galaxies with anaverage velocity of 11,467 km/s located to the NE of the assumedcentroid of A2151, where early and late type galaxies share the samedynamical properties. The implications of this result for the nature andidentification of the x-ray source is briefly discussed.
| Galaxy structures in the Hercules region
216 redshifts have been obtained in a region of 981 sq deg south of theHercules supercluster. 172 of these redshifts are of galaxies withmpg less than or equal to 15.1, 110 of which had no previousvelocity measurement. 44 new redshifts are of galaxies fainter thanmpg = 15.1. With these new data we have been able to define asample in a vast region (approximately 1700 sq deg) around Herculeslimited to mpg less than or equal to 15.1 with a velocitycompleteness of 81.5%. 189 galaxies have been morphologically classifiedso that all galaxies in the sample with known velocity now also haveknown morphology. The magnitude limited sample, including 556 galaxies,is then used to identify and describe galaxy structures in the region.We find that the overdense volume is small, that its overall appearanceis that of a coral branch floating in a sea of nothing and that earlyand late type galaxies defined different structures.
| Dark matter and dynamics in the Hercules Cluster (A2151)
New 21-cm observations of faint spiral galaxies in the Hercules cluster(A2151) are presented in order to investigate the dynamics throughoutthe cluster core, out to a projected radius of 1.8/h Mpc. The globaldynamical mass of Hercules is calculated using the virial theorem andthe projected mass estimator. These masses lie in the range 3-9 x 10 exp14 solar masses. The importance of subclustering in A2151 by eye isexamined via the statistical test of Dressler & Shectman (1988), andby considering the effects of the detected substructure on the dynamicalmass determination. The clumpy distribution is interpreted as a signthat the galaxies in the cluster have not reached dynamical equilibriumin the gravitational potential.
| A catalog of galaxies in Hercules from the Palomar Sky Survey and the Minnesota Automated Plate Scanner
The development of galaxies catalogs from the Palomar Sky Survey usingthe Minnesota Automated Plate Scanner (APS) is examined. The design andoperation of APS are described. The algorithm used to distinguish starsfrom galaxies is discussed, and the completeness and confusion of thealgorithm as a function of magnitude are estimated. The quality of thephotometric calibration for galaxy magnitudes and surface-brightnessthresholds is evaluated. The relation between the distribution of colorsand morphological types is studied. The luminosity functions forHercules galaxies are calculated and presented. The catalog generatedusing the APS is 80 percent complete; photometry good to 0.23 mag rms ispossible; and J-F colors are good to 0.17 mag rms.
| 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.
| Notes on the Hercules Galaxy Cluster
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971PASP...83..320C&db_key=AST
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