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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.
|An image database. II. Catalogue between δ=-30deg and δ=70deg.|
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
|The Tully-Fisher relation of the IRAS minisurvey galaxies|
We investigated the possible influence on the Tully-Fisher relation ofactive massive star formation in IRAS galaxies, in order to estimate thecontribution of star formation to their near-infrared luminosity. Weobserved 60 galaxies from the infrared complete so- called IRASMinisurvey sample in the 21 cm H1 line at Arecibo, determined thenear-infrared (H-band) Tully-Fisher relation for the 36 objects in thesample we judged to be usable for this purpose, and compared thisrelation with that of optically selected normal galaxies. The resultsshow no significant enhancement of the near- infrared luminosities ofthe IRAS Minisurvey galaxies compared to those of the optically selectednormal glaxies. From these results we inferred that in the minisurveygalaxies the average contribution of the active massive star formationto the total near-infrared luminosity is less and that exponential decaytimes for the starbursts occurring in the Minisurvey galaxies are of theorder of 10 Myr. The Tully-Fisher relation shows one exceptional galaxy(IRAS 03565+2139) with an about 25 times higher luminosity than averagefor its rotational velocity.
|A survey of the Pisces-Perseus supercluster. VI - The declination zone +15.5 deg to 21.5 deg|
New results are presented of Arecibo observations in the 21 cm line of765 galaxies with declinations between 15.5 deg and 21.5 deg, in thePisces-Perseus supercluster zone. If considered independently on theneighboring parts of sky, this region, to the South of the superclusterridge, shows significantly less evidence of structure on large scales inexcess of 30 Mpc, contrasting substantially with the characteristics ofthe declination zones immediately to the North.
|A list of some corrections to Zwicky's Catalogue of Galaxies and Clusters of Galaxies|
|The radio properties of galaxies with high far-infrared luminosities|
Observations have been made with the Very Large Array, mainly at 5 GHz,of a sample of galaxies with high far-infrared luminosities selectedfrom the Infrared Astronomical Satellite (IRAS) minisurvey. The surfacebrightnesses of the minisurvey sources are greater than those of thedisks of normal galaxies but are similar to those of the central radiosources in these galaxies; the minisurvey sources, however, have muchlarger luminosities and physical sizes than these central sources. Onthe basis of the available data at all wavelengths, it is concluded thatthe far-infrared and radio emission from the minisurvey galaxies iscaused by star formation, not by active nuclei. It is found that thesize of the radio source is inversely correlated with the 60-100 microncolor temperature but is independent of the far-infrared luminosity.
|Near-infrared observations of IRAS minisurvey galaxies|
Near-infrared photometry was obtained for 82 galaxies from the InfraredAstronomy Satellite (IRAS) minisurvey, a sample of infrared selectedgalaxies. The near-infrared colors of these galaxies are similar tothose of normal field spiral galaxies, but cover a larger range in J - Hand H - K. There is evidence of a tighter correlation between the nearand far infrared emission than exists between far-infrared and thevisible emission. These results suggest that hot dust emissioncontributes to the 2.2 micron luminosity, and extinction by dust affectsboth the near-infrared colors and the visible luminosities. In addition,there is an indication that the far-infrared emission in many of theminisurvey galaxies is coming from a strong nuclear component.
|Identification of infrared sources in the IRAS circulars|
From IRAS (Infrared Astronomical Satellite) Circulars Nos. 4 to 15, 110infrared sources have been identified. Out of these 110 identifiedsources 99 are galaxies, nine are nebulae, one is a dark object, and oneis a non-stellar object. Thirty-five of these galaxies, have alreadybeen studied, mostly are spiral type. The characteristics of sixty-fourremaining galaxies, for which the type is not known or uncertain, arestudied by comparing their colors and luminosities with known galaxies.The galaxies observed by IRAS are mostly active galaxies.
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