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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).
| 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
| A Minnesota Automated Plate Scanner Catalog of Galaxies behind the Virgo Cluster and toward Its Antipode
We present a catalog of 1268 galaxies, essentially complete to B <=17.0, found by scanning glass copies of several fields of the originalPalomar Sky Survey using the Minnesota Automated Plate Scanner in itsisodensitometric mode (as opposed to the threshold densitometric modeused in the APS Catalog of the POSS I). In addition to the differentscanning mode, we have employed a different star-galaxy separationmethod and have visually inspected POSS prints to verify that each imageremaining in the catalog is nonstellar. The scanned fields aredistributed generally in two areas, one around the outskirts of theVirgo Cluster, the other toward the antipode of the cluster (but stillin the northern celestial hemisphere). The catalog gives the position ofthe center of each galaxy; estimates of the blue and red magnitudeswithin the outermost threshold crossing and of the blue magnitudeextrapolated to zero surface brightness; and the blue and red diametersof four ellipses fitted to the four threshold crossings (approximately23.8,23.6,23.2, and 22.7 mag arcsec 2 in blue, and 22.5,22.4,21.5, and21.2 mag arcsec^-2^ in red), and the ellipticities of those fourellipses. The catalog has served as a base from which to draw targetsfor a Tully-Fisher study of the Virgocentric infall velocity of theLocal Group.
| H I 21 centimeter observations and I-band CCD surface photometry of spiral galaxies behind the Virgo Cluster and toward its antipode
Sample selection, radio and optical data acquisition and reduction, andobservation results are presented for spiral galaxies behind the VirgoCluster and toward its antipode. I-band CCD photometry was obtained forall the bright galaxies and part of the sample of faint galaxies in thetwo local volumes was studied. The statistical properties of the galaxysamples are discussed.
| Kinematic regulation of star formation in interacting galaxies
Kinematic data for a geometrically-selected set of spiral galaxies inpairs are presented, and analyzed for correlations between indicators ofstar formation and indices of orbital type and extent of kinematicdisturbance. Both nuclear and global star formation rate are connectedto kinematic disturbance with the kind and degree of disturbance moreimportant than either projected separation or relative directions ofgalaxy spin and companion orbit. Enhanced star formation is found forgalaxies with large areas of solid-body rotation and for galaxies withmore general kinds of disturbed velocity structure, with the highestlevels occurring in a set of galaxies distinguished by anomalously smalloverall velocity amplitude. The strongest correlation is between starformation rate (SFR) and amplitude of velocity disturbance, fromrotation curves, when the velocity disturbance is scaled by the galaxyrotation velocity. Triggered star formation is more sensitive to galaxydynamics than to strictly local phenomena such as cloud disruptionvelocities. Comparsion with various models for the enhanced SFR ininteracting systems shows that cloud-collision processes cannot accountfor the strong starbursts in retrograde systems, and models relying oninteractions between different phases of the interstellar mediumsimilarly require too many direct collisions between galaxy disks.Schemes involving gravitational instability of the disk driven initiallyby the external perturbation fare best; such instability can then drivethe rates of other processes such as cloud collisions, possibly in acascadelike series. Solid-body kinematics appear more important than thepresence of a stellar bar in this connection. Using a new set ofclassifications from uniform CCD images, there is a better correlationbetween disturbed kinematics and morphological disturbance of individualgalaxies than with pair interaction types in the Karachentsev catalog,though the relationship is not one-to-one. There is a substantialpopulation of pairs with disturbed kinematics but not disturbed forms.The kinds of disturbance found from direct and retrograde encountersmatch well the predictions of n-body calculations for each kind ofencounter.
| An extragalactic database. I - The Catalogue of Principal Galaxies
The Catalogue of Principal Galaxies is described, which lists equatorialcoordinates (for the equinoxes 1950 and 2000) and cross-identificationsfor 73,197 galaxies. The 40,932 coordinates have standard deviationssmaller than 10 arcsec. A total of 131,601 names from the 38 most commonsources are listed. In addition, mean data for each object are givenwhen available: 49,102 morphological descriptions, 52,954 apparent majorand minor axes, 67,116 apparent magnitudes, 20,046 radial velocities and24,361 position angles. This information was used for facilitatingproper identification. Finally, distribution options are explained.
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