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On the Relation between Circular Velocity and Central Velocity Dispersion in High and Low Surface Brightness Galaxies
In order to investigate the correlation between the circular velocityVc and the central velocity dispersion of the spheroidalcomponent σc, we analyzed these quantities for a sampleof 40 high surface brightness (HSB) disk galaxies, eight giant lowsurface brightness (LSB) spiral galaxies, and 24 elliptical galaxiescharacterized by flat rotation curves. Galaxies have been selected tohave a velocity gradient <=2 km s-1 kpc-1 forR>=0.35R25. We used these data to better define theprevious Vc-σc correlation for spiralgalaxies (which turned out to be HSB) and elliptical galaxies,especially at the lower end of the σc values. We findthat the Vc-σc relation is described by alinear law out to velocity dispersions as low as σc~50km s-1, while in previous works a power law was adopted forgalaxies with σc>80 km s-1. Ellipticalgalaxies with Vc based on dynamical models or directlyderived from the H I rotation curves follow the same relation as the HSBgalaxies in the Vc-σc plane. On the otherhand, the LSB galaxies follow a different relation, since most of themshow either higher Vc or lower σc withrespect to the HSB galaxies. This argues against the relevance of baryoncollapse to the radial density profile of the dark matter halos of LSBgalaxies. Moreover, if the Vc-σc relation isequivalent to one between the mass of the dark matter halo and that ofthe supermassive black hole, then these results suggest that the LSBgalaxies host a supermassive black hole (SMBH) with a smaller masscompared to HSB galaxies with an equal dark matter halo. On the otherhand, if the fundamental correlation of SMBH mass is with the halocircular velocity, then LSB galaxies should have larger black holemasses for a given bulge dispersion. Elliptical galaxies withVc derived from H I data and LSB galaxies were not consideredin previous studies.Based on observations made with European Southern Observatory telescopesat the Paranal Observatory under programs 67.B-0283, 69.B-0573, and70.B-0171.
| The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%
The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
| BVRI surface photometry of mixed morphology pairs of galaxies. I. The first data set
We present multicolor broad band (BVRI) photometry for a sample of 11mixed morphology (E/S0+S) binary galaxies drawn from the KarachentsevCatalogue of Isolated Pairs of Galaxies (KPG). The data is part of anobservational programme devoted to the systematic photometric study ofone of the most complete and homogeneous pair samples available in theliterature. We present B band, B-filtered images, B, V, R and I surfacebrightness and (B-V), (B-R) and (B-I) color profiles as well asgeometric (epsilon = 1 - b/a, PA and a4/a) profiles for eachcomponent pair. In addition, integrated corrected B, V, R and Imagnitudes and integrated (B-V), (B-R) and (B-I) colors are alsopresented. Internal and external data comparisons show consistencywithin the estimated errors. Most of this subsample have photometricparameters homogeneously derived for the first time. Geometric profilesfrom our surface photometry along with the broad-band imaging and colorinformation have been used to re-evaluate morphology in all pairs. Wefind an important number of true mixed pairs with 5/11 (E+S) pairs inthe present sample. The remaining objects include 3 disky pairs(composed of S0 and S members), 2 early-type pair comprising E and S0members and 1 spiral-irregular pair. The measurements will be used in aseries of forthcoming papers where we try to identify and isolate themain structural and photometric properties of disk and ellipticalgalaxies at different stages of interaction.Based on data obtained at the 0.84 m and 1.5 m telescopes of theObservatorio Astronómico Nacional, San Pedro Mártir, BajaCalifornia, México, operated by the Instituto deAstronomía, UNAM.Tables 1-3 and Figs. 5 to 15 are only available in electronic form athttp://www.edpsciences.org
| Local velocity field from sosie galaxies. I. The Peebles' model
Pratton et al. (1997) showed that the velocity field around clusterscould generate an apparent distortion that appears as tangentialstructures or radial filaments. In the present paper we determine theparameters of the Peebles' model (1976) describing infall of galaxiesonto clusters with the aim of testing quantitatively the amplitude ofthis distortion. The distances are determined from the concept of sosiegalaxies (Paturel 1984) using 21 calibrators for which the distanceswere recently calculated from two independent Cepheid calibrations. Weuse both B and I-band magnitudes. The Spaenhauer diagram method is usedto correct for the Malmquist bias. We give the equations for theconstruction of this diagram. We analyze the apparent Hubble constant indifferent regions around Virgo and obtain simultaneously the Local Groupinfall and the unperturbed Hubble constant. We found:[VLG-infall = 208 ± 9 km s-1] [\log H =1.82 ± 0.04 (H ≈ 66 ± 6 km s-1Mpc-1).] The front side and backside infalls can be seenaround Virgo and Fornax. In the direction of Virgo the comparison ismade with the Peebles' model. We obtain: [vinfall} =CVirgo/r0.9 ± 0.2] withCVirgo=2800 for Virgo and CFornax=1350 for Fornax,with the adopted units (km s-1 and Mpc). We obtain thefollowing mean distance moduli: [μVirgo=31.3 ± 0.2(r=18 Mpc )] [μFornax=31.7 ± 0.3 (r=22 Mpc). ] Allthese quantities form an accurate and coherent system. Full Table 2 isonly available 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/393/57
| Position-velocity diagrams of ionized gas in the inner regions of disk galaxies
We use long-slit spectroscopy along the major axis of a sample of 23nearby disk galaxies to study the kinematic properties of theionized-gas component in their inner regions. For each galaxy, we derivethe position-velocity diagram of the ionized gas from its emissionlines. We discuss the variety of shapes observed in suchposition-velocity diagrams by comparing the gas velocity gradient,velocity dispersion and integrated flux measured in the inner (r =~+/-1'') and outer regions (r =~ +/-4''). This kind of analysis allowsthe identification of galaxies which are good candidates to host acircumnuclear Keplerian gaseous disk rotating around a central massconcentration, and to follow up with Hubble Space Telescopeobservations. Based on observations carried out at European SouthernObservatory (ESO N.58, A-0564), at the Multiple Mirror Telescope, whichis a joint facility of the Smithsonian Institution and the University ofArizona, and at the Isaac Newton Telescope operated by the Isaac Newtongroup at the La Palma island at the Spanish Observatorio del Roque delos Muchachos of the Instituto de Astrofisica de Canarias.
| Kinematics of Gas and Stars in 20 Disc Galaxies
In this paper we present the kinematics of the gas and/or the stars of asample of 20 disc galaxies. We investigate whether there is any relationbetween the kinematics of the gas and stars and the classicalmorphological type of the galaxies in the sample. We deduce that, inmost of the late-type spirals we have studied, the stars and the ionizedgas are moving with virtually circular velocity, except when thespectroscopic slit crosses a bar region. On the other hand, we found inthe central parts of early-type disc galaxies a wider variety ofdifferent behaviour of stars and gas. We find many possible factors thatcomplicate the classification of the kinematical properties of thegalaxies by their morphological type: the presence of counter-rotations(star vs. stars or star vs. gas), misalignment between the differentkinematic components present in the galaxy, the presence of a barstructure and its orientation with respect to the line of nodes of thegalaxy, and interactions and mergers or external accretion processes aresome of the problems we find in the study of the kinematics of a galaxy.
| The Frequency of Active and Quiescent Galaxies with Companions: Implications for the Feeding of the Nucleus
We analyze the idea that nuclear activity, either active galactic nuclei(AGNs) or star formation, can be triggered by interactions by studyingthe percentage of active, H II, and quiescent galaxies with companions.Our sample was selected from the Palomar survey and avoids selectionbiases faced by previous studies. This sample was split into fivedifferent groups, Seyfert galaxies, LINERs, transition galaxies, H IIgalaxies, and absorption-line galaxies. The comparison between the localgalaxy density distributions of the different groups showed that in mostcases there is no statistically significant difference among galaxies ofdifferent activity types, with the exception that absorption-linegalaxies are seen in higher density environments, since most of them arein the Virgo Cluster. The comparison of the percentage of galaxies withnearby companions showed that there is a higher percentage of LINERs,transition galaxies, and absorption-line galaxies with companions thanSeyfert and H II galaxies. However, we find that when we consider onlygalaxies of similar morphological types (elliptical or spiral), there isno difference in the percentage of galaxies with companions amongdifferent activity types, indicating that the former result was due tothe morphology-density effect. In addition, only small differences arefound when we consider galaxies with similar Hα luminosities. Thecomparison between H II galaxies of different Hα luminositiesshows that there is a significantly higher percentage of galaxies withcompanions among H II galaxies with L(Hα)>1039 ergss-1 than among those with L(Hα)<=1039ergs s-1, indicating that interactions increase the amount ofcircumnuclear star formation, in agreement with previous results. Thefact that we find that galaxies of different activity types have thesame percentage of companions suggests that interactions betweengalaxies is not a necessary condition to trigger the nuclear activity inAGNs. We compare our results with previous ones and discuss theirimplications.
| Kinematic properties of gas and stars in 20 disc galaxies
Ionized gas and stellar kinematical parameters have been measured alongthe major axis of 20 nearby disc galaxies. We discuss the properties ofeach sample galaxy, distinguishing between those characterized byregular or peculiar kinematics. In early-type disc galaxies, ionized gastends to rotate faster than stars and to have a lower velocitydispersion (Vg > Vstar and sigmag< sigmastar), whereas in late-type spirals, gas andstars show almost the same rotation velocities and velocity dispersions(Vg =~ Vstar and sigmag =~sigmastar ). Incorporating the early-type disc galaxiesstudied by Bertola et al. (1995), Fisher (1997) and Corsini et al.(1999), we have compiled a sample of some 40 galaxies for which themajor-axis radial profiles of both the stellar and gaseous componentshave been measured. The value of sigmastar measured atRe/4 turns out to be strongly correlated with the galaxymorphological type, while sigmag is not and sometimes takesvalues above the range expected from thermal motions or small-scaleturbulence. Based on observations carried out at the European SouthernObservatory, at the Multiple Mirror Telescope Observatory, at theObservatorio del Roque de los Muchachos, at the Observatorio del Teide,and at the Mount Graham International Observatory. Tables 5 and 6 areonly available 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/374/394
| Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| Kinematics of gas and stars in spiral galaxies.
Not Available
| 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
| Search and Redshift Survey for IRAS Galaxies behind the Milky Way and Structure of the Local Void
This is the third and final paper of our systematic visual search forIRAS galaxies behind the Milky Way at |b| <= 15 deg. This paperpresents a catalog of 950 IRAS galaxies with 60 mu m flux densitieslarger than 0.6 Jy located between l = 0 deg and 150 deg, of which 293are newly identified by this search. We made a redshift survey for theidentified galaxies and obtained new redshift data of 171 galaxies. Wealso present newly measured redshifts of 27 IRAS galaxies between l =150 deg and 225 deg at |b| <= 15 deg. In this paper we studied thestructure of the Local void using IRAS galaxies and galaxies from theThird Reference Catalogue of Bright Galaxies in the region l = 30deg--120 deg and b = -50 deg to +30 deg. The center of the Local voidturned out to be located at l ~ 60 deg, b ~ -15 deg, and cz ~ 2500 kms-1, and the size is about 2500 km s-1 along the direction toward thecenter.
| Optical and I-band surface photometry of spiral galaxies. I. The data.
We present V- and I-band CCD surface photometry on 234 inclined Sa-Sdgalaxies, completed by similar data in B and R for a reduced subsample.In this first paper of a series, the reduction of the data is discussed,and several comparisons are made with other recent works. Radialprofiles are presented for the surface brightness and thecharacteristics of ellipses fitted to isophotes; global, effective, andisophotal parameters are listed. All the results are available inelectronic form.
| 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.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| UBVR photometry and rotation of late-type galaxies - NGC 959, 1156, 1160, 6643, and 7292
Brightness and color distribution profiles for five late-type galaxiesobtained from observations with the magnetic-focusing image tube arepresented. Rotation curves and density distribution models are derivedas well. A comparison of photometric and kinematic data shows that thestellar population content changes slowly with the galactocentricdistance. Density depression in the central parts of the disk is neededto explain the rotation curves of three out of the five galaxies underconsideration.
| IRAS Faint Source Catalogue, version 2.0.
Not Available
| Observations of binary galaxies at a frequency of 102 MHz
A total of 93 double galaxies from the Karachentsev list was observedwith the large phased array at the Lebedev Physical Institute at 102MHz. The interplanetary oscillation method was used. Two of the galaxieswere found to contain scintillating components with angular dimensionsof less than 1 arcsec and flux densities of more than 1 Jy. Theobservations of double galaxies at low radio frequencies indicate thatgalaxies in pairs are more active than single galaxies.
| Double galaxy investigations. I - Observations
Redshift information from 240 A/mm spectrograms is presented for 370double arcsec galaxy systems from the Karachentsev (1972) catalog,including all pairs in that catalog with separation less than 80 arcsec.An extensive error discussion utilizing internal and external (21 cm)comparisons provides calibration of systematic error and determines theuncertainty for a typical high weight optical redshift to be plus orminus 65 km/sec. Internal differential redshifts within single spectrausing common lines achieve accuracies of 18-30 km/sec, depending uponseparation, and are available for about 200 pairs. Extensive informationon emission and other properties is also provided.
| The Perseus supercluster
Results are presented of a redshift survey of galaxies with photographicmagnitudes less than or equal to 14.0 located between 0 h 15 min and 3 h20 min RA and 26 and 45 deg dec, the region identified with the Perseussupercluster. New redshifts are reported for 116 galaxies, and arecombined with literature data to obtain values for a total of 141galaxies in the region. Morphological classifications, diameters,position angles and ellipticities are also presented for all 141galaxies. The 116 galaxies in the sample with radial velocities between3700 and 9000 km/sec are found to form a supercluster with a filamentarystructure including the Perseus, A347, A262, NGC 383 and NGC 507clusters and with a mean velocity of 5327 km/sec. It is estimated thatsuperclusters occupy approximately 1% of the universe, with a mean freepath between superclusters of 285/h Mpc. Results support the view thatcluster- and supercluster-mass clouds fragment before galaxies andcommunicate anisotropic matter and velocity distributions to galaxies.The results are also noted to be consistent with intrinsic galacticredshifts and band structure.
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