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A catalog of warps in spiral and lenticular galaxies in the Southern hemisphere
A catalog of optical warps of galaxies is presented. This can beconsidered complementary to that reported by Sánchez-Saavedra etal. (\cite{sanchez-saavedra}), with 42 galaxies in the northernhemisphere, and to that by Reshetnikov & Combes(\cite{reshetnikov99}), with 60 optical warps. The limits of the presentcatalog are: logr 25 > 0.60, B_t< 14.5, delta (2000) <0deg, -2.5 < t < 7. Therefore, lenticular galaxies havealso been considered. This catalog lists 150 warped galaxies out of asample of 276 edge-on galaxies and covers the whole southern hemisphere,except the Avoidance Zone. It is therefore very suitable for statisticalstudies of warps. It also provides a source guide for detailedparticular observations. We confirm the large frequency of warpedspirals: nearly all galaxies are warped. The frequency and warp angle donot present important differences for the different types of spirals.However, no lenticular warped galaxy has been found within the specifiedlimits. This finding constitutes an important restriction fortheoretical models.
| Warps and correlations with intrinsic parameters of galaxies in the visible and radio
From a comparison of the different parameters of warped galaxies in theradio, and especially in the visible, we find that: a) No large galaxy(large mass or radius) has been found to have high amplitude in thewarp, and there is no correlation of size/mass with the degree ofasymmetry of the warp. b) The disc density and the ratio of dark toluminous mass show an opposing trend: smaller values give moreasymmetric warps in the inner radii (optical warps) but show nocorrelation with the amplitude of the warp; however, in the externalradii is there no correlation with asymmetry. c) A third anticorrelationappears in a comparison of the amplitude and degree of asymmetry in thewarped galaxies. Hence, it seems that very massive dark matter haloeshave nothing to do with the formation of warps but only with the degreeof symmetry in the inner radii, and are unrelated to the warp shape forthe outermost radii. Denser discs show the same dependence.
| 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.
| Box- and peanut-shaped bulges. I. Statistics
We present a classification for bulges of a complete sample of ~ 1350edge-on disk galaxies derived from the RC3 (Third Reference Catalogue ofBright Galaxies, de Vaucouleurs et al. \cite{rc3}). A visualclassification of the bulges using the Digitized Sky Survey (DSS) inthree types of b/p bulges or as an elliptical type is presented andsupported by CCD images. NIR observations reveal that dust extinctiondoes almost not influence the shape of bulges. There is no substantialdifference between the shape of bulges in the optical and in the NIR.Our analysis reveals that 45% of all bulges are box- and peanut-shaped(b/p). The frequency of b/p bulges for all morphological types from S0to Sd is > 40%. In particular, this is for the first time that such alarge frequency of b/p bulges is reported for galaxies as late as Sd.The fraction of the observed b/p bulges is large enough to explain theb/p bulges by bars. Partly based on observations collected at ESO/LaSilla (Chile), DSAZ/Calar Alto (Spain), and Lowell Observatory/Flagstaff(AZ/U.S.A.). Tables 6 and 7 are only available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The I-Band Tully-Fisher Relation for SC Galaxies: 21 Centimeter H I Line Data
A compilation of 21 cm line spectral parameters specifically designedfor application of the Tully-Fisher (TF) distance method is presentedfor 1201 spiral galaxies, primarily field Sc galaxies, for which opticalI-band photometric imaging is also available. New H I line spectra havebeen obtained for 881 galaxies. For an additional 320 galaxies, spectraavailable in a digital archive have been reexamined to allow applicationof a single algorithm for the derivation of the TF velocity widthparameter. A velocity width algorithm is used that provides a robustmeasurement of rotational velocity and permits an estimate of the erroron that width taking into account the effects of instrumental broadeningand signal-to-noise. The digital data are used to establish regressionrelations between measurements of velocity widths using other commonprescriptions so that comparable widths can be derived throughconversion of values published in the literature. The uniform H I linewidths presented here provide the rotational velocity measurement to beused in deriving peculiar velocities via the TF method.
| The I-Band Tully-Fisher Relation for SC Galaxies: Optical Imaging Data
Properties derived from the analysis of photometric I-band imagingobservations are presented for 1727 inclined spiral galaxies, mostly oftypes Sbc and Sc. The reduction, parameter extraction, and errorestimation procedures are discussed in detail. The asymptotic behaviorof the magnitude curve of growth and the radial variation in ellipticityand position angle are used in combination with the linearity of thesurface brightness falloff to fit the disk portion of the profile. TotalI-band magnitudes are calculated by extrapolating the detected surfacebrightness profile to a radius of eight disk scale lengths. Errors inthe magnitudes, typically ~0.04 mag, are dominated by uncertainties inthe sky subtraction and disk-fitting procedures. Comparison is made withthe similar imaging database of Mathewson, Ford, & Buchhorn, both aspresented originally by those authors and after reanalyzing theirdigital reduction files using identical disk-fitting procedures. Directcomparison is made of profile details for 292 galaxies observed incommon. Although some differences occur, good agreement is found,proving that the two data sets can be used in combination with onlyminor accommodation of those differences. The compilation of opticalproperties presented here is optimized for use in applications of theTully-Fisher relation as a secondary distance indicator in studies ofthe local peculiar velocity field.
| 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.
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| 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.
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| A Survey for H 2O Megamasers in Active Galactic Nuclei. II. A Comparison of Detected and Undetected Galaxies
A survey for H2O megamaser emission from 354 active galaxies hasresulted in the detection of 10 new sources, making 16 known altogether.The galaxies surveyed include a distance-limited sample (coveringSeyferts and LINERs with recession velocities less than 7000 km s-1) anda magnitude-limited sample (covering Seyferts and LINERs with mB <=14.5). In order to determine whether the H2O-detected galaxies are"typical" active galactic nuclei (AGNs) or have special properties thatfacilitate the production of powerful masers, we have accumulated adatabase of physical, morphological, and spectroscopic properties of theobserved galaxies. The most significant finding is that H2O megamasersare detected only in Seyfert 2 and LINER galaxies, not Seyfert 1's. Thislack of detection in Seyfert 1's indicates either that they do not havemolecular gas in their nuclei with physical conditions appropriate toproduce 1.3 cm H2O masers or that the masers are beamed away from Earth,presumably in the plane of the putative molecular torus that hides theSeyfert 1 nucleus in Seyfert 2's. LINERs are detected at a similar rateto Seyfert 2's, which constitutes a strong argument that at least somenuclear LINERs are AGNs rather than starbursts, since starbursts havenot been detected as H2O megamasers. We preferentially detect H2Oemission from the nearer galaxies and from those that are apparentlybrighter at mid- and far-infrared and centimeter radio wavelengths.There is also a possible trend for the H2O-detected galaxies to be moreintrinsically luminous in nuclear 6 cm radio emission than theundetected ones, though these data are incomplete. We find evidence thatSeyfert 2's with very high (NH > 1024 cm-2) X-ray--absorbing columnsof gas are more often detected as H2O maser emitters than Seyfert 2'swith lower columns. It may be that the probability of detecting H2Omaser emission in Seyfert galaxies increases with increasing column ofcool gas to the nucleus, from Seyfert 1's through narrow-line X-raygalaxies to Seyfert 2's.
| Optical Rotation Curves and Linewidths for Tully-Fisher Applications
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2402C&db_key=AST
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| A Survey for H 2O Megamasers in Active Galactic Nuclei. I. Observations
We report an extensive search for 22 GHz H_2_O maser emission fromnearby active galaxies. Our sample includes all Seyfert and LINERgalaxies listed in the Huchra catalog or the Veron-Cetty & Veroncatalog with recessional velocities less than 7000 km s^-1^, and allSeyfert galaxies and LINERs in Huchra's catalog with m_b_ <= 14. Inaddition to these distance- and magnitude-limited samples, we have alsoobserved a number of active galaxies, including radio galaxies, athigher redshift; In all, some 354 galaxies have been surveyed. Ten newH_2_O megamaser sources have been detected, resulting in 16 galaxiesthat are currently known to contain H_2_O masers with isotropicluminosities greater than 20 L_sun_. Of the observed active galaxieswith cz < 7000 km s^-1^, 5.4% have detectable H_2_O megamaseremission. This fraction increases to 11% for those sources with cz <2000 km s^-1^. The newly discovered megamaser sources were monitored onsubsequent observing runs. The strength of the maser features varies forthese sources, as they do for Galactic masers. Three of the galaxieshave sufficient data to test for velocity changes of narrow masercomponents comparable in magnitude to those of the well-studied systemicfeatures in NGC 4258. The maser line in one of these galaxies-NGC2639-is found to have a systematic redward velocity drift of 6.6 +/- 0.4km s^-1^ yr^-1^. No systematic velocity drifts are found for the othertwo sources. We also report large apparent velocity changes in theunusual broad H_2_O emission feature in NGC 1052.
| 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.
| Rotation Curves of 967 Spiral Galaxies
We present the rotation curves of 967 southern spiral galaxies, obtainedby deprojecting and folding the raw Hα data originally publishedby Mathewson, Ford, & Buchhorn (1992). For 900 objects, we alsopresent, in figures and tables, the rotation curves smoothed on scalescorresponding to 5%-20% of the optical size; of these, 80 meet objectiveexcellence criteria and are suitable for individual detailed massmodeling, while 820, individually less compelling mainly because of themoderate statistics and/or limited extension, are suitable forstatistical studies. The remaining 67 curves suffer from severeasymmetries, small statistics, and large internal scatter that maylargely limit their use in galaxy structure studies. The deprojectedfolded curves, the smoothed curves, and various related quantities areavailable via anonymous ftp at galileo.sissa.it in the directory/users/ftp/pub/psrot.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| The Montreal blue galaxy survey. I - First list of ultraviolet-bright candidates
The first results of a UV-bright galaxy survey using theMontreal-Cambridge-Tololo (MCT) plate collection are presented. Visualinspection of 57 CTIO Curtis Schmidt plates, cnvering more than 1300 sqdeg, has resulted in the identification of 95 UV-bright galaxiesbrighter than B = 15.5. Even though 80 percent of these objects are IRASsources, barely 20 percent have their nature already established. Theinitial result of our survey shows that the bulk of our UV-brightcandidates are narrow emission-line galaxies commonly known as starburstor H II galaxies. The fraction of AGNs found is somewhat less than 10percent, but comparable to what has been found by the Markarian survey.
| A southern sky survey of the peculiar velocities of 1355 spiral galaxies
The paper presents data from photometric and spectroscopic observationsof 1355 southern spiral galaxies and uses them to determine theirdistances and peculiar velocities via the Tully-Fisher (TF) relation.I-band CCD surface photometry was carried out using the 1-m and 3.9-mtelescopes at Siding Spring Observatory. H-alpha rotation curves for 965galaxies and 551 H I profiles are presented. The physical parameters,photometric and velocity data, distances, and peculiar velocities of thegalaxies are presented in tabular form. The mean distance, systemicvelocity, and average peculiar velocity of 24 clusters in the sample aregiven. TF diagrams are presented for each cluster.
| Southern Sky Redshift Survey - The catalog
The catalog of radial velocities for galaxies which comprise thediameter-limited sample of the Southern Sky Redshift Survey ispresented. It consolidates the data of observations carried out at theLas Campanas Observatory, Observatorio Nacional, and South AfricanAstronomical Observatory. The criteria used for the sample selection aredescribed, as well as the observational procedures and the techniqueutilized to obtain the final radial velocities. The intercomparisonbetween radial velocity measurements from different telescopes indicatesthat the final data base is fairly homogeneous with a typical error ofabout 40 km/s. The sample is at present 90 percent complete, and themissing galaxies are predominantly objects with very low surfacebrightness for which it is very difficult to obtain optical redshifts.
| Studies of nearby poor clusters - The Eridanus group
Results are reported from dynamical study of the Eridanus group ofgalaxies. This system is quite prominent in one of the large-scalefeatures found in the recently completed Southern Sky Redshift Survey(da Costa et al., 1988): the Eridanus-Fornax-Dorado filament. Theirregualr aspect of Eridanus suggests the existence of subclustering,which is confirmed by statistical tests. These subclusters are bound,suggesting that the system is still condensing from the Hubble flow andmay eventually form a cluster of about 10 to the 14th solar mass. Bycalculating the two-body orbital solution, it is found that the Eridanuscomplex and the Fornax cluster also form a bound system, although stillin the expansion phase.
| The Southern Supercluster
The Southern Supercluster is described using data compiled from fivecatalogs, reduced to a homogeneous system following RC2. In terms ofmass, luminosity, and mass-to-light ratio, the Southern Superclustercompares well with the Coma and Hercules superclusters, but is lessmassive than the Local Supercluster. It is shown that, even though theSouthern Supercluster is the nearest supercluster to the LocalSupercluster, it is well separated from the Local Supercluster. However,there is evidence of a tenuous stream of galaxies connecting theSouthern Supercluster with the Perseus Supercluster.
| The ON-CfA redshift survey of the southern hemisphere
A redshift survey of a diameter-limited sample of southern galaxies hasbeen performed by the Observatorio Nacional in collaboration with theHarvard-Smithsonian Center for Astrophysics. Redshift data are presentedfor 442 galaxies. A relatively small mean difference of -5.2 km/s wasfound between the present redshifts and previous radio data.
| A catalogue of Seyfert galaxies.
Not Available
| New southern galaxies with active nuclei
A list of AGN candidates, identified from optical spectra taken as partof an ongoing redshift survey of southern galaxies, is presented. Theidentification, coordinates, morphological type, measured heliocentricradial velocity, and proposed emission type are given for the galaxiesshowing evidence of nonstellar nuclear activity. Using standarddiagnostics, several new Seyferts and low-ionization nuclear-emissionregions (LINERs) are identified among the emission-line galaxiesobserved.
| Southern Galaxy Catalogue.
Not Available
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