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|Galaxies with Rows|
The results of a search for galaxies with straight structural elements,usually spiral-arm rows (“rows” in the terminology ofVorontsov-Vel'yaminov), are reported. The list of galaxies that possess(or probably possess) such rows includes about 200 objects, of whichabout 70% are brighter than 14m. On the whole, galaxies with rows makeup 6 8% of all spiral galaxies with well-developed spiral patterns. Mostgalaxies with rows are gas-rich Sbc-Scd spirals. The fraction ofinteracting galaxies among them is appreciably higher than amonggalaxies without rows. Earlier conclusions that, as a rule, the lengthsof rows are similar to their galactocentric distances and that theangles between adjacent rows are concentrated near 120° areconfirmed. It is concluded that the rows must be transient hydrodynamicstructures that develop in normal galaxies.
|Arcsecond Positions of UGC Galaxies|
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
|The Luminosity-Metallicity Relation for Bulges of Spiral Galaxies|
Optical integrated spectra of bulges have been obtained for 28 spiralgalaxies for which the surface brightness profiles were decomposed intodisk and bulge contributions by Kent (ApJS, 59, 115(1985)] and Simien& de Vaucouleurs [ApJ, 302, 564 (1986)]. By applying an appropriateaperture size for each galaxy, the unavoidable contamination of diskstarlight has been carefully minimized and set to ~1/7 of the totalstellar light. The sample covers a wide range in bulge luminosity andmorphology. The Mg_2_ index shows a tight correlation with the bulgeintrinsic luminosity, similar-and extended at fainter magnitudes-to therelationship known for ellipticals. Other features such as CaII K, CN,G- band, and TiO show similar trend with the bulge luminosity. On thecontrary, the Fe5270 and Fe5335 iron lines are constant-within somedispersion-for all bulges. A simple application of a stellar populationsynthesis model suggests that magnesium should be most enhanced withrespect to iron in the brightest bulges. Concerning the structuralparameters, bulges do occupy the same region in the fundamental plane asellipticals. In conclusion, the present study favors the idea that thebulk of stars in bulges have formed with only moderate or negligibleinfluence of the disk material, likely by very similar processes asthose driving the formation of elliptical galaxies.
|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.
|High signal-to-noise ratio observations of H I in 243 galaxies|
The 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts.
|CCD surface photometry of field Galaxies. II - Bulge/disk decompositions|
Major- and minor-axis profiles given previously for 105 galaxies of allmorphological types are decomposed into bulge and disk components. Inaddition, three model-independent parameters which measure the meansurface brightness, scale radius, and degree of light concentration arederived. The best correlations are found between Hubble type,concentration, bulge/disk ratio, and mean surface brightness.Correlations between the individual bulge and disk parameters generallyshow large scatter. The properties of S0 galaxies are inconsistent withtheir having been formed from spiral galaxies via gas depletion; theirproperties are intermediate between those of ellipticals and spirals.Most elliptical galaxies probably do not form by the merging of diskgalaxies. The difficulty of distinguishing between elliptical and S0galaxies in some cases is emphasized.
|Supplement to the detailed bibliography on the surface photometry of galaxies|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...60..517P&db_key=AST
|On the cigar-shaped ring galaxies|
In light of the ongoing debate as to whether cigar-shaped or 'spindle'ring galaxies have an oblate or prolate central body, photographic andspectroscopic data are presented and discussed. Ring galaxy parametersand redshifts are shown, and the flattening distribution for the mainparts of the ring galaxies is compared with that found by de Vaucouleurs(1959) for E galaxies. Specific attention is given to the ring galaxyNGC 2685. It is concluded that central structures of both oblate andprolate types evidently exist.
|CCD surface photometry of field galaxies. I - Observations|
Images of 105 galaxies selected from a larger complete sample ofintrinsically luminous galaxies have been obtained for the purpose ofcomputing surface brightness profiles. The intensity profiles along themajor and minor axes are computed by a method in which ellipticalcontours whose position angle and ellipticity are allowed to vary withradius are fitted to the true isophotes of a galaxy. The resultingprofiles and ellipse parameters are listed for each object. An extensivecomparison of the present photometry with that of other workers is madeto assess the reliability of the data. For most objects, additionalphotometric information is given, including an isophotal radius andmagnitude within a limiting isophote of 24.0 mag/sq arcsec, anapproximate total magnitude, the effective radius containing one-halfthe total light, and the mean surface brightness inside this radius. Afull analysis of the data is deferred to a second paper where theprofiles will be decomposed into bulge and disk components.
|A 21 centimeter line survey of a complete sample of interacting and isolated galaxies|
The paper presents 21 cm line observations of a complete sample ofinteracting and isolated galaxies made with the National Radio AstronomyObservatory 91 and 43 m telescopes and the Arecibo 3035 m telescope. The21 cm line data are combined with a homogeneous set of optical data onangular diameters, axial ratios, magnitudes, and colors, and integralproperties are calculated for the galaxies in both samples. In thispaper, the sample selection procedures, the method of observation, thedata reduction, and the observational errors are described. Thedetection percentages are presented for both samples.
|A survey of galaxy redshifts. IV - The data|
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
|The Morphology of Galaxies. III. Diffuse Matter in Spherical Stellar Systems|
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