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Spectrophotometry of galaxies in the Virgo cluster. II. The data
Drift-scan mode (3600-6800 Å) spectra with 500
| 1.65-μm (H -band) surface photometry of galaxies - VIII. The near-IR κ space at z =0
We present the distribution of a statistical sample of nearby galaxiesin the κ -space (κ 1 ~logM , κ 2~logI e 3 M /L , κ 3 ~logM /L ).Our study is based on near-IR (H -band: λ =1.65μm)observations, for the first time comprising early- and late-typesystems. Our data confirm that the mean effective dynamicalmass-to-light ratio M /L of the E+S0+S0a galaxies increases withincreasing effective dynamical mass M , as expected from the existenceof the Fundamental Plane relation. Conversely, spiral and Im/BCDgalaxies show a broad distribution in M /L with no detected trend of M/L with M , the former galaxies having M /L values about twice largerthan the latter, on average. For all the late-type galaxies, the M /Lincreases with decreasing effective surface intensity I e ,consistent with the existence of the Tully-Fisher relation. Theseresults are discussed on the basis of the assumptions behind theconstruction of the κ -space and their limitations. Our study iscomplementary to a previous investigation in the optical (B -band:λ =0.44μm) and allows us to study wavelength dependences ofthe galaxy distribution in the κ -space. As a first result, wefind that the galaxy distribution in the κ 1 -κ2 plane reproduces the transition from bulgeless tobulge-dominated systems in galaxies of increasing dynamical mass.Conversely, it appears that the M /L of late-types is higher (lower)than that of early-types with the same M in the near-IR (optical). Theorigins of this behaviour are discussed in terms of dust attenuation andstar formation history.
| 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.
| 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 (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| 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 Universality of the Fundamental Plane of E and S0 Galaxies: Spectroscopic Data
We present central velocity dispersion measurements for 325 early-typegalaxies in eight clusters and groups of galaxies, including newobservations for 212 galaxies. The clusters and groups are the A262,A1367, Coma (A1656), A2634, Cancer, and Pegasus Clusters and the NGC 383and NGC 507 Groups. The new measurements were derived frommedium-dispersion spectra that cover 600 Å centered on the Mg I btriplet at lambda ~ 5175 Å. Velocity dispersions were measuredusing the Tonry & Davis cross-correlation method, with a typicalaccuracy of 6%. A detailed comparison with other data sources is made.
| 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.
| ROSAT PSPC observations of 5 X-ray bright early type galaxies.
We report on the ROSAT PSPC observations of 5 X-ray bright early-typegalaxies. Their X-ray morphology is more complex than Einstein data hadshown, ranging from the ellipsoidal shape of NGC 533 to the ~200kpc tailof NGC 7619. Hot gas at an average temperature of 0.8-1keV dominatestheir X-ray emission. The spectral analysis is based on the assumptionof a hot thin plasma at cosmic abundances, since the spectral resolutionof the PSPC does not allow unambiguous measures of the model parameters(temperatures, low energy cut-off, metal abundance). However, theestimated temperature are not strongly affected by this choice. Atemperature distribution of the hot interstellar medium is also derived.Higher temperatures are in some cases observed at larger radii, whilethe innermost 1' region is cooler in all of the objects studied. Due tothe large range in distances however this corresponds to significantlydifferent galaxy radii, from 5kpc in NGC 4649 to 30kpc in NGC 533. Thetemperature and density distributions derived are used to estimate thetotal mass of these systems, which span fromM_T_~10^12^-10^13^Msun_ and corresponding mass-to-lightratios M/L~10-150 in solar units. Formal errors on the derived massesare estimated to be >25%. Care must be taken in comparing results fordifferent systems, since some of the emission attributed to theseobjects could suffer from the contribution for the groups and clustersthey belong to. Accordingly, our mass estimates could reflect the effectof the cluster/group potential.
| 1.65μm (H-band) surface photometry of galaxies. II. Observations of 297 galaxies with the TIRGO 1.5m telescope.
We present near-infrared H-band (1.65μm) surface photometry of 297galaxies (mostly) in the Coma Supercluster obtained with the ArcetriNICMOS3 camera, ARNICA, mounted on the Gornergrat Infrared Telescope.Magnitudes and diameters within the 21.5mag/arcsec^2^ isophote,concentration indices, and total H magnitudes are derived. Combiningthese observations with those obtained similarly using the Calar Altotelescopes (Paper I, 1996A&AS..120..489G) we find a strong positivecorrelation between the near-infrared concentration index and the galaxyH-band luminosity, and we analyze the consequent dependence ofnear-infrared growth-curves on H-band luminosity.
| 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.
| Multifrequency windows on spiral galaxies. II - The A262 and Cancer clusters
New photometrical data (U,B,V and H bands) are presented for about 100spiral galaxies in the A262 and Cancer clusters. The data are used tostudy the dependence of radio continuum to H band and FIR to H bandratios on the color index U - B, taken as an indicator of the starformation history in galaxy disks. Both parameters are found to increasein bluer galaxies, in agreement with the results obtained for otherclusters or field galaxies. The radio continuum activity of spiralgalaxies in the Cancer cluster is not enhanced like in other clusterspirals. A study of the reliability of CCD surface photometry isreported, based on the comparison of two sets of observations obtainedwith different telescopes.
| Near infrared observations of galaxies in the Coma supercluster and in the Cancer cluster. II
New near infrared observations of 110 galaxies in the Coma/A1367supercluster region, and 40 galaxies in the Cancer cluster arepresented. These observations are part of an ongoing investigation ofthe properties of normal galaxies and of their near-IR emission, whichaims at obtaining homogeneous, multifrequency data for a large sample ofgalaxies in different density environments. The addition of theseobservations to the sample presented in Gavazzi and Trinchieri (1989)raises the number of Coma/A1367 galaxies with near-IR data to 275. Themeasurements, together with data published by Bothun et al. (1985), givea sample of 45 spirals in the Cancer cluster.
| The Cancer Cluster - an unbound collection of groups
A surface density contour map of the Cancer Cluster derived from galaxycounts in the Zwicky catalog is presented. The contour map shows thatthe galaxy distribution is clumpy. When this spatial distribution iscombined with nearly complete velocity information, the clumps stand outmore clearly; there are significant differences in the mean velocitiesof the clumps which exceed their internal velocity dispersions. TheCancer Cluster is not a proper 'cluster' but is a collection of discretegroups, each with a velocity dispersion of approximately 300 km/s,separating from one another with the cosmological flow. Themass-to-light ratio for galaxies in the main concentration isapproximately 320 solar masses/solar luminosities (H0 = 100km/s Mpc).
| New radial velocities of galaxies from image-tube spectra.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971AJ.....76..409K&db_key=AST
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