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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.
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| 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
| Accurate Positions for MCG Galaxies
We have measured accurate celestial coordinates for 4741 extragalacticobjects, primarily drawn from a list of MCG galaxies with no recentlypublished accurate positions. The standard deviations in the newpositions depend slightly on the measurement method but are on the orderof 1.0" to 1.2". Standard deviations in the original MCG positions areconfirmed to be at the 1.5′-2.0′ level. These new positionswere integrated into NED in 1997 December.
| 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.
| 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.
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