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Rotational Widths for Use in the Tully-Fisher Relation. I. Long-Slit Spectroscopic Data
We present new long-slit Hα spectroscopy for 403 noninteractingspiral galaxies, obtained at the Palomar Observatory 5 m Hale telescope,which is used to derive well-sampled optical rotation curves. Becausemany of the galaxies show optical emission features that aresignificantly extended along the spectrograph slit, a technique wasdevised to separate and subtract the night sky lines from the galaxyemission. We exploit a functional fit to the rotation curve to identifyits center of symmetry; this method minimizes the asymmetry in thefinal, folded rotation curve. We derive rotational widths using bothvelocity histograms and the Polyex model fit. The final rotational widthis measured at a radius containing 83% of the total light as derivedfrom I-band images. In addition to presenting the new data, we use alarge sample of 742 galaxies for which both optical long-slit and radioH I line spectroscopy are available to investigate the relation betweenthe H I content of the disks and the extent of their rotation curves.Our results show that the correlation between those quantities, which iswell established in the case of H I-poor galaxies in clusters, ispresent also in H I-normal objects: for a given optical size, starformation can be traced farther out in the disks of galaxies with largerH I mass.
| Kinematics of the local universe . XII. 21-cm line measurements of 586 galaxies with the new Nançay receiver
This paper presents 586 new 21-cm neutral hydrogen line measurementscarried out with the FORT receiver of the meridian transit Nançayradiotelescope in the period July 2000-March 2003. This observationalprogramme is part of a larger project aiming at collecting an exhaustiveand magnitude-complete HI extragalactic catalogue for Tully-Fisherapplications. It is associated with the building of the MIGALEspectroscopic archive and database.Tables 2, 3 and HI-profiles and corresponding comments are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/373, or directly atour web site http://klun.obs-nancay.fr
| A search for Low Surface Brightness galaxies in the near-infrared. I. Selection of the sample
A sample of about 3800 Low Surface Brightness (LSB) galaxies wasselected using the all-sky near-infrared (J, H and Ks-band)2MASS survey. The selected objects have a mean central surfacebrightness within a 5'' radius around their centre fainter than 18 magarcsec-2 in the Ks band, making them the lowestsurface brightness galaxies detected by 2MASS. A description is given ofthe relevant properties of the 2MASS survey and the LSB galaxy selectionprocedure, as well as of basic photometric properties of the selectedobjects. The latter properties are compared to those of other samples ofgalaxies, of both LSBs and ``classical'' high surface brightness (HSB)objects, which were selected in the optical. The 2MASS LSBs have aBT_c-KT colour which is on average 0.9 mag bluerthan that of HSBs from the NGC. The 2MASS sample does not appear tocontain a significant population of red objects.All tables and Figs. 2a-c are only available in electronic form athttp://www.edpsciences.org
| Nearby Optical Galaxies: Selection of the Sample and Identification of Groups
In this paper we describe the Nearby Optical Galaxy (NOG) sample, whichis a complete, distance-limited (cz<=6000 km s-1) andmagnitude-limited (B<=14) sample of ~7000 optical galaxies. Thesample covers 2/3 (8.27 sr) of the sky (|b|>20deg) andappears to have a good completeness in redshift (97%). We select thesample on the basis of homogenized corrected total blue magnitudes inorder to minimize systematic effects in galaxy sampling. We identify thegroups in this sample by means of both the hierarchical and thepercolation ``friends-of-friends'' methods. The resulting catalogs ofloose groups appear to be similar and are among the largest catalogs ofgroups currently available. Most of the NOG galaxies (~60%) are found tobe members of galaxy pairs (~580 pairs for a total of ~15% of objects)or groups with at least three members (~500 groups for a total of ~45%of objects). About 40% of galaxies are left ungrouped (field galaxies).We illustrate the main features of the NOG galaxy distribution. Comparedto previous optical and IRAS galaxy samples, the NOG provides a densersampling of the galaxy distribution in the nearby universe. Given itslarge sky coverage, the identification of groups, and its high-densitysampling, the NOG is suited to the analysis of the galaxy density fieldof the nearby universe, especially on small scales.
| 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.
| Constraining the Ages of Supernova Progenitors. I. Supernovae and Spiral Arms
We present the first results of a three-part study of supernova (SN)ages using positional age indicators in spiral galaxies. We havemeasured the positions of 90 Spectroscopically identified Type Ia andType II SNs (SNs Ia and SNs II) relative to spiral arms in their hostgalaxies, making a special effort to reduce inhomogeneity in the processof arm tracing for different galaxies. We find that SNs II are moretightly concentrated to the arms than SNs Ia, but both kinds of SNsoccur closer to arms than a random disk population. However, whencompared with the distribution of V and I light relative to the arms,the SNs Ia are no more tightly concentrated than the general stellarpopulation. This indicates that SNs Ia occur in a population old enoughto have diffused away from their formation regions.
| The Canaris Type IA Supernovae Archive (I)
This paper presents an atlas containing 59 low-resolution supernova
spectra which correspond to 27 type Ia supernovae. These 59spectra spectra which correspond to 27 type Ia supernovae. These 59spectra refer to different ages along the postmaximum type Ia evolution,covering from the photospheric to the old (~>300 days) nebularphases. These supernovae were observed as a part of the long-termobservational program Supernova Monitoring Project, carried out at theObservatorio del Roque de los Muchachos (La Palma, Spain) from 1990 Julyto 1994 July. Most of these observations were taken with the FaintObject Spectrograph (FOS) and a few spectra were obtained by means theISIS spectrograph. Three or more spectra were obtained for ten of thesesupernovae. Concerning the homogeneity among the type Ia supernovasubclass, our sample points to a "first-order" overall homogeneousspectroscopic behavior. However, a finer analysis - comparing spectra atsimilar evolutionary phase-allows differences to be found in relation tostrengths, wavelength positions, and evolution with time of the moresignificant spectral type Ia supernova features. Furthermore, someobjects that exhibit clear signs of spectroscopic peculiarities (SNe1991F, 1991bg, and 1991bj) are also included in our sample. The parentgalaxies of these supernovae present redshifts ranging from z = 0.003 toz = 0.07. Four of these (SNe 1991S, 1991ad, 1992R, and 1992ac) wereobserved in galaxies with z~>0.05. Only six events in our sample weredetected in an early-type (i.e., elliptical or lenticular) galaxy,whereas multiple supernova events were detected in five of the parentgalaxies in our supernova sample.
| 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.
| A catalog of recent supernovae
A listing is given of all supernovae discovered between 1 Jan 1989 and 1Apr 1993. The data show no evidence for a significant dependence of thediscovery probability of supernovae on parent galaxy inclination to theline of sight. If no inclination corrections need to be applied then thesupernova rates in spirals are only about half as large as previouslybelieved. The mean linear separation of supernovae of Type II (SNe II)from the center of their parent galaxy increases with increasingdistance (Shaw effect). The Shaw effect appears less evident, or absent,for (more luminous) supernovae of Type Ia. The data are consistent with,but do not prove, the hypothesis that (presumably reddended) SNe II aremore likely to be discovered in the red than in the blue. Due tointensive surveillance, most bright SNe Ia tend to be found beforemaximum, whereas the majority of faint SNe Ia are discovered aftermaximum light.
| Mean galaxy luminosity classifications
To prepare a catalog of weighted means on the classification system ofvan den Bergh, we have combined eight independent lists of luminosityclass estimates, L. Luminosity class values from each set weretransformed to the standard system and weighted according to the errorsderived through a statistical comparison of L differences betweencatalog pairs. Relations were derived for predicting accidental errorsassociated with galaxy diameter and inclination. In addition, we presentformulas for correcting systematic errors associated with diameter andinclination. Finally, we tabulate a high weight subsample of the meanluminosity classes usable as standards. Most values are tabulated in theThird Reference Catalog of Bright Galaxies.
| Identification of some galaxies as radio sources
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