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Rotational Widths for Use in the Tully-Fisher Relation. I. Long-Slit Spectroscopic Data
We present new long-slit Hα spectroscopy for 403 noninteractingspiral galaxies, obtained at the Palomar Observatory 5 m Hale telescope,which is used to derive well-sampled optical rotation curves. Becausemany of the galaxies show optical emission features that aresignificantly extended along the spectrograph slit, a technique wasdevised to separate and subtract the night sky lines from the galaxyemission. We exploit a functional fit to the rotation curve to identifyits center of symmetry; this method minimizes the asymmetry in thefinal, folded rotation curve. We derive rotational widths using bothvelocity histograms and the Polyex model fit. The final rotational widthis measured at a radius containing 83% of the total light as derivedfrom I-band images. In addition to presenting the new data, we use alarge sample of 742 galaxies for which both optical long-slit and radioH I line spectroscopy are available to investigate the relation betweenthe H I content of the disks and the extent of their rotation curves.Our results show that the correlation between those quantities, which iswell established in the case of H I-poor galaxies in clusters, ispresent also in H I-normal objects: for a given optical size, starformation can be traced farther out in the disks of galaxies with largerH I mass.
| Galaxy Luminosity Functions from Deep Spectroscopic Samples of Rich Clusters
Using a new spectroscopic sample and methods accounting forspectroscopic sampling fractions that vary in magnitude and surfacebrightness, we present R-band galaxy luminosity functions (GLFs) for sixnearby galaxy clusters with redshifts of 4000 kms-1
| A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
A catalog of optical warps of galaxies is presented. This can beconsidered complementary to that reported by Sánchez-Saavedra etal. (\cite{sanchez-saavedra}), with 42 galaxies in the northernhemisphere, and to that by Reshetnikov & Combes(\cite{reshetnikov99}), with 60 optical warps. The limits of the presentcatalog are: logr 25 > 0.60, B_t< 14.5, delta (2000) <0deg, -2.5 < t < 7. Therefore, lenticular galaxies havealso been considered. This catalog lists 150 warped galaxies out of asample of 276 edge-on galaxies and covers the whole southern hemisphere,except the Avoidance Zone. It is therefore very suitable for statisticalstudies of warps. It also provides a source guide for detailedparticular observations. We confirm the large frequency of warpedspirals: nearly all galaxies are warped. The frequency and warp angle donot present important differences for the different types of spirals.However, no lenticular warped galaxy has been found within the specifiedlimits. This finding constitutes an important restriction fortheoretical models.
| Warps and correlations with intrinsic parameters of galaxies in the visible and radio
From a comparison of the different parameters of warped galaxies in theradio, and especially in the visible, we find that: a) No large galaxy(large mass or radius) has been found to have high amplitude in thewarp, and there is no correlation of size/mass with the degree ofasymmetry of the warp. b) The disc density and the ratio of dark toluminous mass show an opposing trend: smaller values give moreasymmetric warps in the inner radii (optical warps) but show nocorrelation with the amplitude of the warp; however, in the externalradii is there no correlation with asymmetry. c) A third anticorrelationappears in a comparison of the amplitude and degree of asymmetry in thewarped galaxies. Hence, it seems that very massive dark matter haloeshave nothing to do with the formation of warps but only with the degreeof symmetry in the inner radii, and are unrelated to the warp shape forthe outermost radii. Denser discs show the same dependence.
| Box- and peanut-shaped bulges. I. Statistics
We present a classification for bulges of a complete sample of ~ 1350edge-on disk galaxies derived from the RC3 (Third Reference Catalogue ofBright Galaxies, de Vaucouleurs et al. \cite{rc3}). A visualclassification of the bulges using the Digitized Sky Survey (DSS) inthree types of b/p bulges or as an elliptical type is presented andsupported by CCD images. NIR observations reveal that dust extinctiondoes almost not influence the shape of bulges. There is no substantialdifference between the shape of bulges in the optical and in the NIR.Our analysis reveals that 45% of all bulges are box- and peanut-shaped(b/p). The frequency of b/p bulges for all morphological types from S0to Sd is > 40%. In particular, this is for the first time that such alarge frequency of b/p bulges is reported for galaxies as late as Sd.The fraction of the observed b/p bulges is large enough to explain theb/p bulges by bars. Partly based on observations collected at ESO/LaSilla (Chile), DSAZ/Calar Alto (Spain), and Lowell Observatory/Flagstaff(AZ/U.S.A.). Tables 6 and 7 are only available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| CCD calibration of the magnitude scale for the SSRS2 sample: The equatorial region
In this paper we continue our investigation on the isophotal nature,accuracy, and uniformity of the magnitude system adopted in the SouthernSky Redshift Survey extension (SSRS2). Extending our earlier work, weexamine galaxies in the equatorial region, primarily in the declinationrange delta greater than or equal to -17.5 deg and less than or equal to0 deg, over a large range of right ascension, covering the southern andnorthern Galactic caps. For this purpose, we have obtained CCD isophotalmagnitudes in the B and R bands for 265 galaxies of differentmorphological types. Using the larger sample we confirm our earlierclaim that the mSSRS2 magnitudes are very nearly themagnitude measured within the isophote muB = 26 mag/sqarcsec, with a dispersion of about 0.30 mag. The relative zero-pointoffset between our mSSRS2 magnitudes and the CCD photometryis -0.02 mag from all data we have obtained. However, we detect avariation of the zero-point across different regions of the sky of +/-0.10 mag for regions at large angular separations. We also estimate thatthe zero-point offset between the mSSRS2 and Zwicky systemsis relatively small (approximately 0.10 mag), which should allow us tocombine the data from the SSRS2 and the CfA2 Redshift Survey.
| The morphological catalogue of galaxies equatorial survey
We present 865 redshifts of galaxies located in the equatorial stripdelta between -17.5 deg and -2.5 deg in the right ascension rangebetween 20 h and 5 h. Redshifts have been obtained for the completesample of all 833 galaxies in the Morphological Catalog of Galaxies withmagnitudes brighter than m = 14.5 (corresponding approximately tom(Zwicky) = 15.0). This sample also includes three galaxies from othersources with more reliable magnitudes, satisfying this limit, and 29fainter galaxies, usually companions of the galaxies in the magnitudelimited sample. Our maps of a very large volume of nearby spacedemonstrate a variety of coherent large scale structures which includelarge voids, 20-50/h Mpc in diameter and large walls at least 70/h Mpcacross.
| 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.
| A dynamical analysis of twelve clusters of galaxies
Four-hundred-twenty-eight new redshift measurements for galaxies in thevicinity of 12 Abell clusters are presented. The data are supplementedby previously published data with 3 deg of each cluster center. Thecluster selection, the variety of telescopes and instrumentation used toobtain the galaxy redshifts, and the available X-ray observations arediscussed. Each cluster is exmained in some detail, with the emphasisplaced on the nature of the observed velocity distributions. Robust andresistant estimators of the velocity location and scale are applied inorder to quantify these distributions. The offset in velocity space ofthe dominant galaxy in each cluster or subcluster is considered withrespect to the central location in the velocity space of the cluster asa whole, and the physical implications of significant offsets found inseveral clusters are discussed. Dynamical estimates of the masses ofclusters and/or subclusters are obtained; for clearly bimodal systems,two-body models are employed to specify their likely dynamical state.
| Southern extension of the Perseus Supercluster?
In order to investigate in 3D the galaxian density enhancement locatedin the south of the Pisces Perseus Supercluster, a redshift survey isconducted of early-type galaxies with a diameter greater than 1 arcminin a region bounded by 20 h and 6 h, and -20 and 0 deg. Data presentedinclude those for 157 radial velocities which, added to all thepreviously known redshifts in this region, show a galaxy distributionconcentrated around 5000 km/s and the presence of a void of about 25/hMpc. These two characteristics are the same as the ones found by Haynesand Giovanelli (1989), in the northern part of the Pisces PerseusSupercluster, suggesting that it could extend toward the south. Acomparison with the recent data obtained in the same region byPellegrini et al. (1990) is presented.
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