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|Total magnitude, radius, colour indices, colour gradients and photometric type of galaxies|
We present a catalogue of aperture photometry of galaxies, in UBVRI,assembled from three different origins: (i) an update of the catalogueof Buta et al. (1995) (ii) published photometric profiles and (iii)aperture photometry performed on CCD images. We explored different setsof growth curves to fit these data: (i) The Sersic law, (ii) The net ofgrowth curves used for the preparation of the RC3 and (iii) A linearinterpolation between the de Vaucouleurs (r(1/4) ) and exponential laws.Finally we adopted the latter solution. Fitting these growth curves, wederive (1) the total magnitude, (2) the effective radius, (3) the colourindices and (4) gradients and (5) the photometric type of 5169 galaxies.The photometric type is defined to statistically match the revisedmorphologic type and parametrizes the shape of the growth curve. It iscoded from -9, for very concentrated galaxies, to +10, for diffusegalaxies. Based in part on observations collected at the Haute-ProvenceObservatory.
|The Catalog of Southern Ringed Galaxies|
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
|Brightest cluster galaxies as standard candles|
We investigate the use of brightest cluster galaxies (BCGs) as standardcandles for measuring galaxy peculiar velocities on large scales. Wehave obtained precise large-format CCD surface photometry and redshiftsfor an all-sky, volume-limited (z less than or = 0.05) sample of 199BCG. We reinvestigate the Hoessel (1980) relationship between the metricluminosity, Lm, within the central 10 kpc/h of the BCGs andthe logarithmic slope of the surface brightness profile, alpha. TheLm-alpha relationship reduces the cosmic scatter inLm from 0.327 mag to 0.244 mag, yielding a typical distanceaccuracy of 17% per BCG. Residuals about the Lm-alpharelationship are independent of BCG luminosity, BCG B - Rccolor, BCG location within the host cluster, and richness of the hostcluster. The metric luminosity is independent of cluster richness evenbefore correcting for its dependence on alpha, which provides furtherevidence for the unique nature of the BCG luminosity function. Indeed,the BCG luminosity function, both before and after application of thealpha-correction, is consistent with a single Gaussian distribution.Half the BCGs in the sample show some evidence of small color gradientsas a function of radius within their central 50 kpc/h regions but withalmost equal numbers becoming redder as becoming bluer. However, withthe central 10 kpc/h the colors are remarkably constant -- the mean B -Rc color is 1.51 with a dispersion of only 0.06 mag. Thenarrow photometric and color distributions of the BCGs, the lack of'second-parameter' effects, as well as the unique rich clusterenvironment of BCGs, argue that BCGs are the most homogeneous distanceindicators presently available for large-scale structure research.
|Parsecscale Radio Cores in Early Type Galaxies|
We find compact (<0.03 arcsec) radio-continuum cores in about 70 percent of radio-emitting elliptical and S0 galaxies over a wide range intotal radio power (10^21^-,10^26^ W Hz^-1^ at 5 GHz). The cores usuallyhave a flat or rising spectrum between 2.3 and 8.4 GHz, with a medianspectral index of + 0.3. Even at low luminosities, the radio emissionfrom most elliptical galaxies appears to be powered by a parsec-scale`engine' like those in classical radio galaxies and quasars. The coreand total radio power are related (P_core_ is proportional toP_total_^0.7^ on average), and the parsec-scale cores of radio galaxiesare typically one hundred times more powerful than those in `normal'giant elliptical galaxies.
|Parkes radio sources in the directions of southern rich clusters|
A listing of all Parkes radio sources coincident within 0.3 clusterradii of southern rich clusters of galaxies studied by Abell et al.(1989) is compiled. A pronounced peak of radio sources very near thecluster centers was found. Bautz Morgan type I clusters tend to havemore powerful radio sources and are radio-load about 5 times more oftenthan clusters without dominant central galaxies. There is no strongcorrelation between radio emission and richness class. It is found thatthe slope of the cluster-radio source two-point angular correlationfunction is twice that of the galaxy-galaxy correlation function.Furthermore, the correlation amplitude for stronger sources (greaterthan 0.65 Jy) is nearly twice that of the entire Parkes catalog samplesuggesting a tighter correlation with cluster centers for the strongersources. Finally, the distribution of spectral indices for Parkessources within ACO clusters is different from that outside the clusters;stronger cluster sources have steeper spectra on average.
|Long-Baseline Interferometry of a Complete Southern Sample of Early-Type Galaxies|
|Low-luminosity radio sources in early-type galaxies|
A sensitive radio continuum survey of 114 nearby E and S0 galaxies hasbeen made to search for weak sources. The radio detection rate is 42percent, with a flux limit of 0.8 mJy at 5 GHz. By deriving the radioluminosity function for a complete sample, it is shown that most brightearly-type galaxies have low-luminosity nonthermal radio sources.Galaxies of similar optical luminosity vary widely in radio luminosity,but a characteristic radio power rises roughly as the optical luminositysquared. S0 galaxies have weaker radio sources on average thanelliptical galaxies, but this can be explained by the low luminosity ofmost S0 bulges relative to ellipticals. No correlation is found betweenradio power and axial ratio for galaxies with radio luminosities below10 to the 23rd W/Hz.
|Mass-losing red giants in open clusters|
Mass-losing stars in open clusters with main-sequence turn-offs atintermediate mass have been searched for by using the IRAS data base.The absence of many strong 60 micron sources in open clusters impliesthat intermediate-mass stars lose much of their mass during an intensewind phase of rather short duration. For stars of about seven solarmasses, this phase, if it exists at all, lasts for not much more than100,000 yr. For stars of about four solar masses, the intense wind phaseappears to last considerably less than 10 million yr; it may well lastfor less than a million yr.
|Southern Galaxy Catalogue.|
|Radio and optical observations of a complete sample of E and SO galaxies. III. A radio continuum survey at 2.7 and 5.0 GHz.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...53S&db_key=AST
|Radio and optical observations of a complete sample of E and SO galaxies. II. UBV aperture photometry.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...34S&db_key=AST
|Radio and optical observations of a complete sample of E and S0 galaxies. I - Radial velocities. II - UBV aperture photometry. III - A radio continuum survey at 2.7 and 5.0 GHz|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...23S&db_key=AST
|Is there a unique relation between absolute (blue) luminosity and total 21 CM linewidth of disk galaxies?|
Twenty-one-cm line observations for a sample of 130 galaxies in nearbygroups and in the Virgo cluster were used together with well-establishedvalues from the literature for a discussion of the blue Tully-Fisherrelation (TFR). Known distances of galaxies from the local group and theM81 group were used to calibrate the zeropoint of the TFR. Within theobservational errors the slope of the TFR was the same for the wholesample, and was only weakly dependent on: (1) the correction used forinternal extinction in the galaxies and (2) the inclusion of a galaxiantype dependence of the TFR. The correlation coefficients between theslope of the TFR and the distance moduli are significant and alwayspositive; distances derived via the TFR do depend on the adopted slope.Known H I profiles of Virgo cluster galaxies were used to check fordifferences in the TFR between group and cluster galaxies. The resultingdistance of the Virgo cluster is 24.0 + or - 3.3 Mpc.
|A distance scale from the infrared magnitude/H I velocity-width relation. IV - The morphological type dependence and scatter in the relation; the distances to nearby groups|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983ApJ...265....1A&db_key=AST
|On the variation of ellipticity with radius in elliptical galaxies|
Ellipticity profiles and isophotal structures of 75 elliptical galaxieswith declinations south of approximately -23 deg are compared. Thesample studied includes both isolated ellipticals and members of pairs,multiplets, groups, and clusters. It is found that: (1) ellipticalgalaxies present four trends as a function of radius, viz., constant,peaked, decreasing, and increasing outward; (2) there is a correlationbetween ellipticity profile and membership in groups or clusters; (3)the brightest ellipticals in rich groups and compact clusters haveellipticity profiles that increase with radius; and (4) rotation of themajor axis of the isophotes is correlated with asymmetry of theisophotes, regardless of the class of ellipticity profile.
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