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CIRS: Cluster Infall Regions in the Sloan Digital Sky Survey. I. Infall Patterns and Mass Profiles
We use the Fourth Data Release of the Sloan Digital Sky Survey (SDSS) totest the ubiquity of infall patterns around galaxy clusters and measurecluster mass profiles to large radii. The Cluster and Infall RegionNearby Survey (CAIRNS) found infall patterns in nine clusters, but thecluster sample was incomplete. Here we match X-ray cluster catalogs withSDSS, search for infall patterns, and compute mass profiles for acomplete sample of X-ray-selected clusters. Very clean infall patternsare apparent in most of the clusters, with the fraction decreasing withincreasing redshift due to shallower sampling. All 72 clusters in awell-defined sample limited by redshift (ensuring good sampling) andX-ray flux (excluding superpositions) show infall patterns sufficient toapply the caustic technique. This sample is by far the largest sample ofcluster mass profiles extending to large radii to date. Similar toCAIRNS, cluster infall patterns are better defined in observations thanin simulations. Further work is needed to determine the source of thisdifference. We use the infall patterns to compute mass profiles for 72clusters and compare them to model profiles. Cluster scaling relationsusing caustic masses agree well with those using X-ray or virial massestimates, confirming the reliability of the caustic technique. Weconfirm the conclusion of CAIRNS that cluster infall regions are wellfitted by Navarro-Frenk-White (NFW) and Hernquist profiles and poorlyfitted by singular isothermal spheres. This much larger sample enablesnew comparisons of cluster properties with those in simulations. Theshapes (specifically NFW concentrations) of the mass profiles agree wellwith the predictions of simulations. The mass in the infall region istypically comparable to or larger than that in the virial region.Specifically, the mass inside the turnaround radius is on average2.19+/-0.18 times that within the virial radius. This ratio agrees wellwith recent predictions from simulations of the final masses of darkmatter halos.
| The Bologna Complete Sample of Nearby Radio Sources
We present a new, complete sample of 95 radio sources selected from theB2 Catolog of Radio Sources and the Third Cambridge Revised Catalog(3CR), with z<0.1. Since no selection effect on the core radio power,jet velocity, or source orientation is present, this sample is wellsuited for statistical studies. In this first paper we present theobservational status of all sources on the parsec (milliarcsecond) andkiloparsec (arcsecond) scale; we give new parsec-scale data for 28sources and discuss their parsec-scale properties. By combining thesedata with those in the literature, information on the parsec-scalemorphology is available for a total of 53 radio sources with differentradio power and kiloparsec-scale morphologies. We investigate theirproperties. We find a dramatically higher fraction of two-sided sourcesin comparison with that of previous flux-limited VLBI surveys.
| A sample of X-ray emitting normal galaxies from the BMW-HRI Catalogue
We obtained a sample of 143 normal galaxies with X-ray luminosity in therange 1038{-}1043 erg s-1 from thecross-correlation of the ROSAT HRI Brera Multi-scale Wavelet (BMW-HRI)Catalogue with the Lyon-Meudon Extragalactic Database (LEDA). We findthat the average X-ray properties of this sample are in good agreementwith those of other samples of galaxies in the literature. We selected acomplete flux limited serendipitous sample of 32 galaxies from which wederived the log N-log S distribution of normal galaxies in the fluxrange 1.1{-} 110 × 10-14 erg cm-2s-1. The resulting distribution is consistent with theEuclidean -1.5 slope. Comparisons with other samples, such as theExtended Medium Sensitivity Survey, the ROSAT All Sky Survey, theXMM-Newton/2dF survey, and the Chandra Deep Field Survey indicate thatthe log N -log S distribution of normal galaxies is consistent with aEuclidean slope over a flux range of about 6 decades.
| A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| Mass Profile of the Infall Region of the Abell 2199 Supercluster
Using a redshift survey of 1323 galaxies (1092 new or remeasured) in aregion of 95 deg2 centered on the nearby galaxy cluster Abell2199, we analyze the supercluster containing A2199, A2197, and an X-raygroup. The caustic technique accurately reproduces the true massprofiles of simulated simple superclusters (i.e., superclusters forwhich the virial mass of one cluster is 2-10 times the virial mass ofall other clusters in the supercluster). We calculate the masses of thetwo main components of A2197 (A2197W and A2197E) by using archival X-rayobservations and demonstrate that the A2199 supercluster is simple (themass of A2199 is 5 and 12 times larger than A2197W and A2197E,respectively) and thus that the caustic technique should yield anaccurate mass profile. The masses of A2199, A2197W, and A2197E withinr500 (the radius within which the enclosed density is 500times the critical density) are 22.0, 3.8, and 1.7 times 1013h-1 Msolar, respectively. The mass profile isuncertain by ~30% within 3 h-1 Mpc and by a factor of 2within 8 h-1 Mpc and is one of only a few for a superclusteron such large scale. Independent X-ray mass estimates agree with ourresults at all radii where they overlap. The mass profile stronglydisagrees with an isothermal sphere profile but agrees with profilessuggested by simulations. We discuss the interplay of the superclusterdynamics and the dynamics of the bound subclusters. The agreementbetween the infall mass profile and other techniques shows that thecaustic technique is surprisingly robust for simple superclusters.
| 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.
| A Test for Large-Scale Systematic Errors in Maps of Galactic Reddening
Accurate maps of Galactic reddening are important for a number ofapplications, such as mapping the peculiar velocity field in the nearbyuniverse. Of particular concern are systematic errors which vary slowlyas a function of position on the sky, as these would induce spuriousbulk flow. We have compared the reddenings of Burstein & Heiles (BH)and those of Schlegel, Finkbeiner, & Davis (SFD) to independentestimates of the reddening, for Galactic latitudes |b|>10^deg. Ourprimary source of Galactic reddening estimates comes from comparing thedifference between the observed B-V colors of early-type galaxies, andthe predicted B-V color determined from the B-V-Mg_2 relation. We havefitted a dipole to the residuals in order to look for large-scalesystematic deviations. There is marginal evidence for a dipolar residualin the comparison between the SFD maps and the observed early-typegalaxy reddenings. If this is due to an error in the SFD maps, then itcan be corrected with a small (13%) multiplicative dipole term. Weargue, however, that this difference is more likely to be due to a small(0.01 mag) systematic error in the measured B-V colors of the early-typegalaxies. This interpretation is supported by a smaller, independentdata set (globular cluster and RR Lyrae stars), which yields a resultinconsistent with the early-type galaxy residual dipole. BH reddeningsare found to have no significant systematic residuals, apart from theknown problem in the region 230^deg
| Optical and CO Radio Observations of Poor Cluster Zwicky 1615.8+3505
The cluster Zwicky 1615.8+3505 is considered to be a dynamically youngpoor cluster. To investigate the morphology and star-formation activityof galaxies under the environment of a dynamically young poor cluster,we have performed V, R, and I surface photometry, optical low-resolutionspectroscopy, and 12CO (J=1-0) line observations for membergalaxies. Our data show that more than 90% of the observed galaxies showregular morphologies and no star-formation activities, indicating thatthe environment does not affect these galaxy properties. Among sixteengalaxies observed, only NGC 6104 shows a significant star-formationactivity, and shows a distorted morphology, indicating a tidalinteraction. This galaxy contains double knots, and only one knotpossesses Seyfert activity, though the sizes and luminosities aresimilar to each other; we also discuss this feature. Based onobservations made at Okayama Astrophysical Observatory (OAO), KisoObservatory (KISO), and Nobeyama Radio Observatory (NRO). KISO isoperated by Institute of Astronomy, School of Science, The University ofTokyo. OAO and NRO are branches of the National AstronomicalObservatory, an inter-university research institute operated by theMinistry of Education, Science, Sports and Culture.
| The peculiar motions of early-type galaxies in two distant regions - II. The spectroscopic data
We present the spectroscopic data for the galaxies studied in the EFARproject, which is designed to measure the properties and peculiarmotions of early-type galaxies in two distant regions. We have obtained1319 spectra of 714 early-type galaxies over 33 observing runs on 10different telescopes. We describe the observations and data reductionsused to measure redshifts, velocity dispersions and the Mgb and Mg_2Lick linestrength indices. Detailed simulations and intercomparison ofthe large number of repeat observations lead to reliable error estimatesfor all quantities. The measurements from different observing runs arecalibrated to a common zero-point or scale before being combined,yielding a total of 706 redshifts, 676 velocity dispersions, 676 Mgblinestrengths and 582 Mg_2 linestrengths. The median estimated errors inthe combined measurements are Delta cz=20 km s^-1, Delta sigma sigma=9.1 per cent, Delta Mgb Mgb=7.2 per cent and Delta Mg_2=0.015 mag.Comparison of our measurements with published data sets shows nosystematic errors in the redshifts or velocity dispersions, and onlysmall zero-point corrections to bring our linestrengths on to thestandard Lick system. We have assigned galaxies to physical clusters byexamining the line-of-sight velocity distributions based on EFAR andZCAT redshifts, together with the projected distributions on the sky. Wederive mean redshifts and velocity dispersions for these clusters, whichwill be used in estimating distances and peculiar velocities and to testfor trends in the galaxy population with cluster mass. The spectroscopicparameters presented here for 706 galaxies combine high-quality data,uniform reduction and measurement procedures, and detailed erroranalysis. They form the largest single set of velocity dispersions andlinestrengths for early-type galaxies published to date.
| Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| The Dynamics of Poor Systems of Galaxies
We assemble and observe a sample of poor galaxy systems that is suitablefor testing N-body simulations of hierarchical clustering and otherdynamical halo models. We (1) determine the parameters of the densityprofile rho(r) and the velocity dispersion profile sigma_p(R), (2)separate emission-line galaxies from absorption-line galaxies, examiningthe model parameters and as a function of spectroscopic type, and (3)for the best-behaved subsample, constrain the velocity anisotropyparameter, beta, which determines the shapes of the galaxy orbits. Oursample consists of 20 systems, 12 of which have extended X-ray emissionin the ROSAT All-Sky Survey. We measure the 877 optical spectra ofgalaxies brighter than m_R~15.4 within 1.5 h^-1 Mpc of the systemcenters (we take H_0=100 h km s^-1 Mpc^-1). Thus, we sample the systemmembership to a radius typically three times larger than other recentoptical group surveys. The average system population is 30 galaxies, andthe average line-of-sight velocity dispersion is ~300 km s^-1. TheNavarro, Frenk, & White universal profile and the Hernquist modelboth provide good descriptions of the spatial data. In most cases anisothermal sphere is ruled out. Systems with declining sigma_p(R) arewell-matched by theoretical profiles in which the star-forming galaxieshave predominantly radial orbits (beta>0) many of these galaxies areprobably falling in for the first time. There is significant evidencefor spatial segregation of the spectroscopic classes regardless ofsigma_p(R).
| A catalogue of Mg_2 indices of galaxies and globular clusters
We present a catalogue of published absorption-line Mg_2 indices ofgalaxies and globular clusters. The catalogue is maintained up-to-datein the HYPERCAT database. The measurements are listed together with thereferences to the articles where the data were published. A codeddescription of the observations is provided. The catalogue gathers 3541measurements for 1491 objects (galaxies or globular clusters) from 55datasets. Compiled raw data for 1060 galaxies are zero-point correctedand transformed to a homogeneous system. Tables 1, 3, and 4 areavailable in electronic form only at the CDS, Strasbourg, via anonymousftp 130.79.128.5. Table 2 is available both in text and electronic form.
| 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 peculiar motions of early-type galaxies in two distant regions. III - The photometric data
We present R-band CCD photometry for 776 galaxies observed in the EFARproject. The photometry is compared with photoelectric data, showingthat a common zero-point good to better than 1 per cent and a precisionof 0.03 mag per zero-point have been achieved. We give the circularlyaveraged surface brightness profiles and the photometric parameters ofthe 762 program galaxies, D(n) diameters, half-luminosity radii, totalmagnitudes, and average effective surface brightnesses. More than 80percent of the profiles have a global S/N ratio larger than 300. Theextrapolation needed to derive total magnitudes is less than 10 percentfor 80 percent of the fits. More than 80 percent of the galaxies havemean effective surface brightness larger than the observed skybrightness. In 90 percent of the profiles the estimate of thecontamination of the sky by the galaxy light is less than 1 percent. Wederive total magnitudes and half-luminosity radii to better than 0.15mag and 25 percent, respectively, for 90 percent of our sample. Incontrast, external comparisons show that data in the literature can bestrongly affected by systematic errors due to large extrapolations,small radial range, sky subtraction errors, seeing effects, and the useof a simple R exp 1/4 fit. The resulting errors can easily amount tomore than 0.5 mag in the total magnitudes and 50 percent in thehalf-luminosity radii.
| Hot coronae in nearby radio galaxies.
We present Rosat X-ray observations (with PSPC and HRI instruments) of asample of radio galaxies belonging to the B2 catalog (3C31, 0206+35,1113+29 and 1553+24). The source 3C31 (B2 0104+32) belongs to the groupArp 331 which shows emission from a diffuse hot intra-group gas and fromthe brightest members of the group. We discuss both the morphologicaland spectral features of this extended region deriving, in the frameworkof an isothermal beta model, the core radius, the central density, themass of the emitting material and gravitational mass, obtainingindications on the presence of dark matter. A comparison of X-ray andradio data shows that the thermal pressure of the external gas exceedsthe minimum pressure of the radio components, apart from the regionclose to the nucleus where the jet is over-pressured. The X-ray emissionfrom the single members of the group and from the other galaxies of thesample are consistent with a thermal spectrum originating from hothalos, which is a common feature in early type galaxies. We discuss themain morphological and physical properties of these coronae.Furthermore, using also the data of previous works, we confirm thestrong correlation between the X-ray and optical luminosities of allthese galaxies.
| The Peculiar Motions of Early-Type Galaxies in Two Distant Regions. I. Cluster and Galaxy Selection
The EFAR project is a study of 736 candidate elliptical galaxies in 84clusters lying in two regions, toward Hercules-Corona Borealis andPerseus-Pisces-Cetus, at distances cz ~ 6000-15,000 km s^-1^. In thispaper (the first of a series), we present an introduction to the EFARproject and describe in detail the selection of the clusters andgalaxies in our sample. Fundamental data for the galaxies and clustersare given, including accurate new positions for each galaxy andredshifts for each cluster. The galaxy selection functions aredetermined by using diameters measured from Schmidt sky survey imagesfor 2185 galaxies in the cluster fields. Future papers in this serieswill present the spectroscopic and photometric observations of thissample, investigate the properties of the fundamental plane forelliptical galaxies, and determine the large- scale peculiar velocityfields in these two regions of the universe.
| Photoelectric UBV Photometry of 179 Bright Galaxies
This paper presents photoelectric UBV multiaperture photometry of 179bright galaxies that was used to compute total magnitudes and colorindices published in the Third Reference Catalog of Bright Galaxies(RC3). The observations were made at the McDonald Observatory from 1983December to 1986 September with an Amperex 56-DVP photometer attached tothe 0.76 and 0.91 m telescopes. The observations can also be used tocalibrate CCD images.
| The fundamental plane of early-type galaxies: stellar populations and mass-to-light ratio.
We analyse the residuals to the fundamental plane (FP) of ellipticalgalaxies as a function of stellar-population indicators; these are basedon the line-strength parameter Mg_2_ and on UBVRI broad-band colors, andare partly derived from new observations. The effect of the stellarpopulations accounts for approximately half the observed variation ofthe mass-to-light ratio responsible for the FP tilt. The residual tiltcan be explained by the contribution of two additional effects: thedependence of the rotational support, and possibly that of the spatialstructure, on the luminosity. We conclude to a constancy of thedynamical-to-stellar mass ratio. This probably extends to globularclusters as well, but the dominant factor would be here the luminositydependence of the structure rather than that of the stellar population.This result also implies a constancy of the fraction of dark matter overall the scalelength covered by stellar systems. Our compilation ofinternal stellar kinematics of galaxies is appended.
| ROSAT observations of the radio galaxy B2 1122+39.
We report X-ray obervations of the radio galaxy B2 1122+39 (NGC 3665),associated with two radio jets, carried out by the Rosat PSPC and HRIinstruments. We have detected extended X-ray emission, with a brightnessprofile consistent with a β hydrostatic model, that originates froma hot corona (kT=~0.5) that surrounds the galaxy. These X-ray data,combined with VLA radio observations, lead to conclude that the thermalpressure of the hot gas is larger than the jet equipartition pressure ofrelativistic electrons, implying that the assumptions made in thecomputation of the internal pressure may not be valid. The jet structurehas been satisfactorily modeled assuming that the jets are confined bythe X-ray emitting atmosphere. We also found that the amount of darkmatter in the galactic corona is negligible.
| A Catalog of Stellar Velocity Dispersions. II. 1994 Update
A catalog of central velocity dispersion measurements is presented,current through 1993 September. The catalog includes 2474 measurementsof 1563 galaxies. A standard set of 86 galaxies is defined, consistingof galaxies with at least three reliable, concordant measurements. It issuggested that future studies observe some of these standard galaxies sothat different studies can be normalized to a consistent system. Allmeasurements are reduced to a normalized system using these standards.
| The CfA Redshift Survey: Data for the NGP +36 Zone
We have assembled redshifts for a complete sample of 719 galaxies withm_zw_ <= 15.5 in the declination range 32.5^deg^ <= δ <=38.5^deg^ and right ascension range 8^h^ <= α <= 17^h^. Wehave determined morphological types for all galaxies in the magnitudelimited sample by direct inspection of the POSS-O plates. 576 of theredshifts are measurements from Mount Hopkins, and 405 are newredshifts. We also include new redshifts for 77 fainter galaxies in thesame strip.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| ROSAT observations of the B2 radio galaxies 1615+35 and 1621+38: implications for the radio source confinement.
We report X-ray observations of the radio galaxies B2 1615+35 (NGC 6109)and B2 1621+38 (NGC 6137), which belong to poor groups of galaxies andare characterized by a "head-tail" structure. We also analyze the X-raybehaviour of the radio galaxy NGC 6107, present within the field of viewand showing a symmetric extended radio structure. The X-ray emissionfrom the group of 1615+35 is complex, including both emission from a hotintergroup gas, and emission from the individual radio galaxies (1615+35itself, which is pointlike, and NGC 6107, which is extended). In thecase of 1621+38, only extended X-ray emission from the galaxy itself isdetected. The extended X-ray emission of the galaxies 1621+38 and NGC6107 is probably related to a gaseous galactic atmosphere. The pointlikeemission of the radio galaxy 1615+35, instead, is likely to originate inthe nucleus. We discuss the confinement of radio components by theambient gas, and find that the external thermal pressure exceeds theinternal equipartition pressure. The X-ray emitting plasma in the1615+35 group is characterized by luminosity, temperature andmetallitcity typical for groups, i.e. lower than for rich clusters. Itstotal mass is ~1/20 of the mass derived assuming hydrostaticequilibrium, implying that this group is likely to be dominated by darkmatter, in agreement with results on other groups. A similar behaviouris found for the two coronas of NGC 6107 and 1621+38.
| 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.
| Photoelectric and CCD photometry of E and S0 galaxies
We present BR photoelectric photometry for 352 E and S0 galaxies thatare part of a large survey of the properties and peculiar motions ofgalaxies in distant clusters. Repeat measurements show our internalerrors to be 2-3 percent in B and R and 1-2 percent in B-R. Comparisonsof BR and BVR reductions for 10 galaxies also observed in V show smallsystematic errors due to differences between the spectral energydistributions of stars and galaxies. External comparisons with B-Vcolors in the literature confirm that these colors are good to 1percent. We also describe R-band CCD observations for 95 of the galaxiesand place these on a BR photometric system for photoelectric and CCDphotomerry, with a common zero-point good to better than 1 percent. Wefind the rms precision of both our photoelectric and CCD R magnitudes tobe 2-3 percent for galaxies as faint as R = 15.
| A revised catalog of CfA1 galaxy groups in the Virgo/Great Attractor flow field
A new identification of groups and clusters in the CfA1 Catalog ofHuchra et al. is presented, using a percolation algorithm to identifydensity enhancements. It is shown that in the resulting catalog,contamination by interlopers is significantly reduced. The Schechterluminosity function is redetermined, including the Malmquist bias.
| KISO survey for ultraviolet-excess galaxies. X.
Presented here are the tenth list and identification charts of theultraviolet-excess galaxies which have been detected on the multi-colorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of some 300 square degrees 490 objects are catalogued downto the photographic magnitude of about 18.
| Groups of galaxies in the Center for Astrophysics redshift survey
By applying the Huchra and Geller (1982) objective group identificationalgorithm to the Center for Astrophysics' redshift survey, a catalog of128 groups with three or more members is extracted, and 92 of these areused as a statistical sample. A comparison of the distribution of groupcenters with the distribution of all galaxies in the survey indicatesqualitatively that groups trace the large-scale structure of the region.The physical properties of groups may be related to the details oflarge-scale structure, and it is concluded that differences among groupcatalogs may be due to the properties of large-scale structures andtheir location relative to the survey limits.
| Spectroscopy and photometry of elliptical galaxies. III - UBV aperture photometry, CCD photometry, and magnitude-related parameters
Photoelectric aperture photometry of nearly 2000 individual observationsof 449 elliptical galaxies combined with published measurements usingthe self-consistent UVB color catalog developed by Burstein et al.(1987) are presented. The data are placed on a standard magnitude andcolor system, and 'total' magnitudes and effective diameters are derivedby comparison with the standard elliptical magnitude growth curve. Agraphical representation of the standard growth curve and the residualsfrom it for each galaxy are given, and a new diameter measurement Dn ispresented which can be measured reliably for elliptical galaxies andserves as an accurate distance indicator when combined with centralvelocity dispersion. Individual magnitudes, surface brightnesses,effective diameters, and values of Dn are summarized for each galaxy incatalog form.
| Spectroscopy and photometry of elliptical galaxies. II - The spectroscopic parameters
Radial velocities, velocity dispersions, and Mg line-strength indicesare measured for 469 elliptical galaxies using four telescope/detectorconfigurations. The data have been put on a common scale; the scatter ofrepeat measurements indicates an uncertainty of + or - 10 percent and +or - 0.01 mag for single determinations of sigma and Mg2, respectively.A correction for the change in linear aperture size as a function ofdistance has been derived, and mean corrected values of sigma and Mg2are adopted. The galaxies have been assigned to groups by combining thepresent velocities with those in the redshift catalog of Huchra et al.(1983) and using the algorithm of Huchra and Geller (1982).
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