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IC 18


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Kinematics of the local universe . XII. 21-cm line measurements of 586 galaxies with the new Nançay receiver
This paper presents 586 new 21-cm neutral hydrogen line measurementscarried out with the FORT receiver of the meridian transit Nançayradiotelescope in the period July 2000-March 2003. This observationalprogramme is part of a larger project aiming at collecting an exhaustiveand magnitude-complete HI extragalactic catalogue for Tully-Fisherapplications. It is associated with the building of the MIGALEspectroscopic archive and database.Tables 2, 3 and HI-profiles and corresponding comments are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/373, or directly atour web site http://klun.obs-nancay.fr

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.

A multicolor photometric study of the tidal features in interacting galaxies
Four-color surface photometry (BVri) is presented forlow-surface-brightness tidal features in interacting galaxies. Objectswere selected on the basis of visual morphology including a crosssection of tails, bridges, plumes, shells, and extended envelopes.Intensity cross sections and surface brightness suggests that plumes areface-on or near face-on sheets; tails and bridges are more nearlyone-dimensional, linear figures. In many cases the colors of tidalfeatures are similar to the outer regions of the primary galaxies,confirming the stripping origin hypothesis. However, large colorvariations are found among the morphological components within mostsystems, and within individual components. Blue colors in primaries andtidal features are most dramatic in B-V, not V-1, indicating that starformation, not metallicity or age, is the dominant component. There isclear evidence in the sample of a correlation between the magnitude ofthe color variation and the time. The color variations are largest ashort time after the beginning of the interaction, and they diminish toa very low level in merged systems. This correlation provides analternate estimator of interaction age in systems with ambiguousmorphologies.

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.

Global properties of interacting disk-type galaxies
Optical, far-IR, and radio observations of global properties arepresented for a sample of strongly interacting disk-type galaxies.Global star formation rates (SFRs) for the galaxies span a large rangeand are, on average, a factor of 2.5 higher than similarly determinedglobal SFRs for isolated spiral galaxies. New star formation occurspreferentially in or near the nuclear regions. H I 21 cm emission-lineprofiles indicate the presence of anomalous velocity material andchaotic patterns of gas motion in many interacting systems. Few systemsshow evidence for the presence of a well-organized rotating H I disksuch as are seen in isolated spiral galaxies. Neutral hydrogen gasmass-to-blue luminosity ratios are not atypical when compared withisolated spirals. The evidence indicates that local rather than globalproperties of these galaxies govern the star-formation process. Theobservations generally support the notion that enhanced SFRs are causedby increased cloud collision rates and dissipative flows of gas to thenucleus.

Atlas of interacting galaxies, Part. II and the concept of fragmentation of galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977A&AS...28....1V&db_key=AST

Galactic Bridges and Tails
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972ApJ...178..623T&db_key=AST

Atlas of Peculiar Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966ApJS...14....1A&db_key=AST

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ICIC 18
HYPERLEDA-IPGC 1759

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