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FLASH redshift survey - I. Observations and catalogue
The FLAIR Shapley-Hydra (FLASH) redshift survey catalogue consists of4613 galaxies brighter than bJ= 16.7 (corrected for Galacticextinction) over a 700-deg2 region of sky in the generaldirection of the Local Group motion. The survey region is a70°× 10° strip spanning the sky from the ShapleySupercluster to the Hydra cluster, and contains 3141 galaxies withmeasured redshifts. Designed to explore the effect of the galaxyconcentrations in this direction (in particular the Supergalactic planeand the Shapley Supercluster) upon the Local Group motion, the 68 percent completeness allows us to sample the large-scale structure betterthan similar sparsely-sampled surveys. The survey region does notoverlap with the areas covered by ongoing wide-angle (Sloan or 2dF)complete redshift surveys. In this paper, the first in a series, wedescribe the observation and data reduction procedures, the analysis forthe redshift errors and survey completeness, and present the surveydata.
| Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic Data
We present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere.
| Redshift-Distance Survey of Early-Type Galaxies: Circular-Aperture Photometry
We present R-band CCD photometry for 1332 early-type galaxies, observedas part of the ENEAR survey of peculiar motions using early-typegalaxies in the nearby universe. Circular apertures are used to tracethe surface brightness profiles, which are then fitted by atwo-component bulge-disk model. From the fits, we obtain the structuralparameters required to estimate galaxy distances using theDn-σ and fundamental plane relations. We find thatabout 12% of the galaxies are well represented by a pure r1/4law, while 87% are best fitted by a two-component model. There are 356repeated observations of 257 galaxies obtained during different runsthat are used to derive statistical corrections and bring the data to acommon system. We also use these repeated observations to estimate ourinternal errors. The accuracy of our measurements are tested by thecomparison of 354 galaxies in common with other authors. Typical errorsin our measurements are 0.011 dex for logDn, 0.064 dex forlogre, 0.086 mag arcsec-2 for<μe>, and 0.09 for mRC,comparable to those estimated by other authors. The photometric datareported here represent one of the largest high-quality and uniformall-sky samples currently available for early-type galaxies in thenearby universe, especially suitable for peculiar motion studies.Based on observations at Cerro Tololo Inter-American Observatory (CTIO),National Optical Astronomy Observatory, which is operated by theAssociation of Universities for Research in Astronomy, Inc., undercooperative agreement with the National Science Foundation (NSF);European Southern Observatory (ESO); Fred Lawrence Whipple Observatory(FLWO); and the MDM Observatory on Kitt Peak.
| 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
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| 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.
| Interstellar Matter in Elliptical Galaxies - Part Three - Properties of Dust Extinction
We have used multicolour CCD surface photometry of 10 ellipticalgalaxies with large-scale dust lanes or rings to investigate thewavelength dependence of the dust extinction. In general, the extinctioncurves are found to run parallel to the Galactic curve of Rieke &Lebofsky. The ratio of total to selective extinction R_V_ is found torange between 2.1 and 3.3, and is lower on average than the canonicalGalactic value of 3.1, implying that the `large' dust grains - which areresponsible for the extinction of optical light - are generally smallerthan in our Galaxy. We show that systematic effects concerning thelocation of the dust within the galaxy body, which may modify theobserved extinction curves, do not change this conclusion. We haveestimated the dust content of the lanes directly from total extinctionvalues (e.g., A_V_), using the observed grain sizes. Extinctionefficiencies of refractory grains and a grain size distribution aretaken from the literature. The dust masses calculated using the totalextinction values turn out to be up to 35 per cent lower than thosecalculated using the Galactic ratio of neutral hydrogen column densityto E(B - V) colour excess, showing that the effect of smaller `large'grain sizes on the total dust mass is significant. We find that thegalaxies with R_V_ values (and, hence, characteristic grain sizes) thatare smaller than in our Galaxy have smooth, regularly distributed dustlanes, whereas the dust in galaxies with `normal' grain sizes istypically much more irregularly distributed, e.g., in patches. Assumingthat the dust in these galaxies has an external origin, this suggeststhat the observed characteristic dust grain size is determined by thetime elapsed since the dust lane was accreted from outside. Followingthe current theoretical model calculations of formation time-scales ofregular dust lanes and rings in early-type galaxies, we predict thatelliptical galaxies containing regular dust lanes with typical dustmasses of 10^6^ - 10^7^ M_sun_ do not contain hot, X-ray- emitting gas.
| The supergalactic plane redshift survey
Redshift measurements, about 1000 of which are new, are presented for1314 galaxies in a survey toward the apex of the large-scale streamingflow for ellipticals. The velocity histogram shows that the excess ingalaxy number counts in this area is due to a substantial concentrationof galaxies with discrete peaks at V about 3000 km/s and V about 4500km/s. After correction for the sampling function, the centroid of thedensity distribution is found to be near V about 4500 km/s.Normalization to the more extensive SSRS survey, which was selected bythe same criteria, shows that the region studied contains a considerableoverdensity of galaxies from 2000 to 6000 km/s. This result is in goodagreement with the 'great attractor' model suggested by Lynden-Bell etal. (1988) which attributes the peculiar motions of elliptical galaxiesover a large region of space to an extensive mass overdensity whichincludes the Hydra-Centaurus and Pavo-Indus superclusters. The centroidof the density enhancement is also consistent with new data by Dresslerand Faber (1990) of peculiar motions of elliptical and spiral galaxies,both of which show a zero crossing of the Hubble line at approximately4500-5000 km/s.
| A southern redshift survey. I - Accurate redshifts for 500 galaxies observed at SAAO
Radial velocities are presented for about 500 galaxies observed with anintensified Reticon photon-counting detector attached to the 1.9 mtelescope at the Sutherland field station of SAAO. The velocities weredetermined by cross correlation with standard velocity templates, fromthe measured wavelengths of emission lines, or from both techniques,with spectra covering the wavelength range from 3700 to 5400 A. Thefinal velocities appear to have the same zero point as H I radiovelocities, and have standard deviations of the order of 35 km/s, thoughcross-correlation velocities on their own may have significantly largererrors.
| Southern Galaxy Catalogue.
Not Available
| A catalog of dusty elliptical galaxies
A catalog of about 100 dusty elliptical galaxies and some relatedobjects is presented. A morphological classification system is proposed,and the observed dust lane characteristics of some of the individualgalaxies are described. The properties of the galaxies are discussed,including the distribution of morphological types, their radioproperties, radio source orientation, neutral hydrogen, kinematics anddynamics, and relationship to other types of peculiar galaxies.
| Catalogue of central velocity dispersions of galaxies
A total of 880 measurements of velocity dispersions for 546 galaxieshave been compiled. These data have been used to look for biasesintroduced by the observational techniques and reduction procedures. Twomain effects have been corrected for, due to the reference and the slitwidth. A catalog of homogeneous data has been compiled, where the rawdata are corrected for these effects.
| Kinematics of elliptical-like galaxies with dust lanes
Spectroscopic observations have been made of four elliptical-likegalaxies which contain strong dust lanes. Stellar rotation curves andvelocity dispersion profiles are presented in at least two positionangles for each galaxy. Spectra taken along the dust lanes also exhibitweak emission lines from which the velocity field of the ionized gas hasbeen determined. In two cases the rotation axes of the stellar andgaseous components are orthogonal. A comparison is made with publishedmodels of tumbling prolate bars and constraints on the maximum figurerotation are derived. The nature of the present sample is brieflydiscussed in the light of these new observations.
| Early-type /discless/ galaxies with dust lanes
A comprehensive, homogeneous sample of 40 optically selected dust-lanegalaxies, which exhibit no obvious associated luminous disks, ispresented along with a preliminary discussion of its properties. Adearth of such galaxies in the north is attributed to the poorerresolution of the Palomar Sky Survey relative to the Southern SkySurvey, which is the source materiaal in the south. It is inferred thatthere may not be a comparably large population of galaxies with dustlanes closely confined to their central regions. The orientation of thedust lanes is varied, but the majority occurs impartially on the majoror minor axes of the light distribution, with a substantial minority ofskew cases with the dust at an intermediate angle. Observed propertiesof the galaxies are summarized, and it is suggested that the propertiesare best attributed to the accretion of cool material at a fairly recentepoch (less than a few x 10 to the 9th yr ago), and that subsequentevolution of this material can explain the observed distribution of dustlane orientation. It is thought that a significant number of early-typegalaxies are prolate in form.
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