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HYPERLEDA. II. The homogenized HI data
After a compilation of HI data from 611 references and new observationsmade in Nançay, we produce a catalog of homogenized HI data for16781 galaxies. The homogenization is made using the EPIDEMIC methodfrom which all data are progressively converted into the adoptedstandard. The result is a catalog giving: 1) the logarithm of twice themaximum rotation velocity, log 2V_Msin i, converted to thesystem of Mathewson et al. (\cite{Mathewson1996}). This quantity isgiven without correction for inclination; 2) the HI magnitude,m21, (area of the 21-cm line width expressed in magnitude)converted to the flux system of Theureau et al. (\cite{Theureau1998});3) the HI velocity, V_HI, expressed with the optical definition (i.e.,using wavelengths instead frequencies). The typical uncertainties are:0.04 for log 2V_Msin i, 0.25 mag for m21 and 9 kms-1 for V_HI.Full Tables \ref{epidemicw}, \ref{epidemicw2}, \ref{epidemicf},\ref{epidemicf2} and Fig. \ref{profiles} are available in electronicform at http://www.edpsciences.org. Full Tables \ref{references},\ref{cataf}, \ref{newdata} and \ref{notes} are available in electronicform at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/412/57
| Near-infrared spectroscopy of starburst galaxies
We present new K-band spectroscopy for a sample of 48 starburstgalaxies, obtained using UKIRT in Hawaii. This constitutes a fair sampleof the most common types of starburst galaxies found in the nearbyUniverse, containing galaxies with different morphologies, masses andmetallicities, with far-infrared luminosityLIR<1010Lsolar. The variety ofnear-infrared spectral features shown by these galaxies impliesdifferent bursts characteristics, which suggests that we survey galaxieswith different star formation histories or at different stages of theirburst evolution. Using synthetic starburst models, we conclude that theensemble of parameters that best describes starburst galaxies in thenearby UniverseQ1 is a constant rate of star formation, a Salpeterinitial mass function (IMF) with an upper mass cut-off ofMup=30Msolar and bursts ages between 10Myr and1Gyr. The model is fully consistent with the differences observed in theoptical and far-infrared (FIR) between the different types ofstarbursts. It suggests that Hii galaxies have younger bursts and lowermetallicities than starburst nucleus galaxies (SBNGs), while luminousinfrared galaxies (LIRGs) have younger bursts but higher metallicities.Although the above solution from the synthetic starburst model is fullyconsistent with our data, it may not constitute a strong constraint onthe duration of the bursts and the IMF. A possible alternative may be asequence of short bursts (which may follow an universal IMF) over arelatively long period of time. In favour of the multiple-bursthypothesis, we distinguish in our spectra some variations ofnear-infrared (NIR) features with the aperture that can be interpretedas evidence that the burst regions are not homogeneous in space andtime. We also found that the burst stellar populations are dominated byearly-type B stars, a characteristic which seems difficult to explainwith only one evolved burst. Our observations suggest that the starburstphenomenon must be a sustained or self-sustained phenomenon: either starformation is continuous in time, or multiple bursts happen in sequenceover a relatively long period of time. The generality of ourobservations implies that this is a characteristic of starburst galaxiesin the nearby Universe.
| Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| 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.
| The Montreal Blue Galaxy survey. 2: Second list of UV-bright candidates
We present and discuss the second list of the Montreal Blue Galaxysurvey. Following the inspection of 71 plates, we found 237 newcandidates with B less than 15.5. 73 percent of them are also detectedby Infrared Astronomy Satellite (IRAS). Spectrophotometry was carriedout, at medium resolution, for a subset of 40 objects leading to theidentification of three new AGNs and producing 13 new radial velocities.Spectral classification of our candidates confirms our previous findingthat the majority of our candidates are starburst nucleus galaxiessimilar to the objects studied by Balzano in 1983. Our survey is biasedagainst the high excitation starburst H II galaxies and the LINERgalaxies. Metallicities of our galaxies are found to be from log(O/H)=8.4 to 9.0, which suggests galaxies in advanced stages of chemicalevolution.
| The morphological catalogue of galaxies equatorial survey
We present 865 redshifts of galaxies located in the equatorial stripdelta between -17.5 deg and -2.5 deg in the right ascension rangebetween 20 h and 5 h. Redshifts have been obtained for the completesample of all 833 galaxies in the Morphological Catalog of Galaxies withmagnitudes brighter than m = 14.5 (corresponding approximately tom(Zwicky) = 15.0). This sample also includes three galaxies from othersources with more reliable magnitudes, satisfying this limit, and 29fainter galaxies, usually companions of the galaxies in the magnitudelimited sample. Our maps of a very large volume of nearby spacedemonstrate a variety of coherent large scale structures which includelarge voids, 20-50/h Mpc in diameter and large walls at least 70/h Mpcacross.
| The optical luminosity function of a 60-micron flux-limited sample of IRAS galaxies
A determination is made of the optical luminosity function (OPLF) of aninfrared flux-limited sample of IRAS galaxies. The sample includes 92objects; among these are an infrared-loud quasar and two previouslyknown Seyferts. The OPLF of the IRAS galaxies in the sample shows thatin the magnitude range between -22 and 18, IRAS galaxies represent about15 percent of field galaxies. At low luminosities, Mj greater than -19mag, there may be a deficiency of IRAS galaxies relative to the fieldgalaxies. The far-IR luminosity function of the sample is also derived;it agrees well with other determinations.
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