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Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| HI Observations of Barred Magellanic Spirals.I.Global Properties
We present observations of the H I content of a sample of BarredMagellanic spiral type galaxies. The data are consistent with the factthat SBm systems are late-type spirals and not irregular galaxies. Thebarred morphology that is evident in the optical structure of thesegalaxies manifests itself in both the distribution and kinematics of theneutral gas. The H I is also distributed well beyond the optical extentof each galaxy. We have detected the presence of small (~10^7^ M_sun_) HI clouds around four of the five galaxies in this sample. Most of theclouds appear to be actively interacting with their primary galaxy andhave no optical counterparts on the Digital Sky Survey images. Wespeculate that the barred morphology and kinematics of these galaxiesmay be the result of their interaction with such neighboring clouds.Additionally, the presence of these clouds and their relationship withthe primary galaxies suggests that the process of galaxy formationcontinues in the present epoch.
| General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| NGC 4027 - an interacting one-armed spiral galaxy with a warped ring
We present high-resolution (VLA C-array) H I observations of the pair ofgalaxies NGC 4027-4027A. The companion galaxy NGC 4027A appears to beundergoing severe tidal stripping, as evidenced by a stream of gas beingtorn out of it. NGC 4027 itself appears to be surrounded by a ring of HI consisting of gas torn out from NGC 4027A in previous orbitalpassages. The ring is warped and inclined to the plane of NGC 4027.Assuming that the H I stream traces the path of the interaction, we useit and the ring to obtain the approximate elements of the orbit of thecompanion. From arguments of dynamical friction we deduce that there isa dark-matter halo around NGC 4027 extending to at least 1.5 times itspresent separation from NGC 4027A. From a 2.1 micron image of the galaxywe determine that in addition to the m = 1 mode there is a significant m= 2 mode. We argue that disk-to-halo mass ratio and disk velocitydispersion allowed both modes to grow through swing amplification, andthat the extraordinary prominence of the m = 1 mode is due to the strongstimulus provided by the close interaction.
| NGC 4027: An Interacting One-Armed Spiral Galaxy
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