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The Westerbork HI survey of spiral and irregular galaxies. III. HI observations of early-type disk galaxies
We present Hi observations of 68 early-type disk galaxies from the WHISPsurvey. They have morphological types between S0 and Sab and absoluteB-band magnitudes between -14 and -22. These galaxies form the massive,high surface-brightness extreme of the disk galaxy population, few ofwhich have been imaged in Hi before. The Hi properties of the galaxiesin our sample span a large range; the average values of MHI/LB and DH I/D25 are comparableto the ones found in later-type spirals, but the dispersions around themean are larger. No significant differences are found between the S0/S0aand the Sa/Sab galaxies. Our early-type disk galaxies follow the same Himass-diameter relation as later-type spiral galaxies, but theireffective Hi surface densities are slightly lower than those found inlater-type systems. In some galaxies, distinct rings of Hi emissioncoincide with regions of enhanced star formation, even though theaverage gas densities are far below the threshold of star formationderived by Kennicutt (1989, ApJ, 344, 685). Apparently, additionalmechanisms, as yet unknown, regulate star formation at low surfacedensities. Many of the galaxies in our sample have lopsided gasmorphologies; in most cases this can be linked to recent or ongoinginteractions or merger events. Asymmetries are rare in quiescentgalaxies. Kinematic lopsidedness is rare, both in interacting andisolated systems. In the appendix, we present an atlas of the Hiobservations: for all galaxies we show Hi surface density maps, globalprofiles, velocity fields and radial surface density profiles.
| On the alignment between binary spiral galaxies
We show some significance against the null hypothesis of randominteractions of binary spiral galaxies, and in favour of the alternativethat more interactions than expected occur for axes either nearlyparallel (spins being parallel or anti-parallel) or nearly orthogonal.We discuss this in the context of similar prior studies, using adifferent statistical focus in such a way that we are able toincorporate additional data.
| 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
| A Kinematic Study of M51-Type Galaxies
Not Available
| Statistical study of M 51-type galaxies
We present a statistical analysis of a new sample of M 51-type galaxies.Using the MCG and VV catalogues, we selected 32 such binary systems. Wefound that a typical M 51-type pair consists of a bright L*spiral galaxy and a satellite with blue luminosity 1/30-1/3 of theprimary one. The main galaxies in such pairs are often barred and havetwo well-defined spiral arms. M 51-type systems show an enhanced starformation rate (from FIR luminosities). We found a weak dependence ofthe star formation rate of the system on relative luminosity of thecompanion. M 51-type galaxies are relatively frequent: about 1/12 of allpairs are of M 51-type.
| 1.65 μm (H-band) surface photometry of galaxies. V. Profile decomposition of 1157 galaxies
We present near-infrared H-band (1.65 μm) surface brightness profiledecomposition for 1157 galaxies in five nearby clusters of galaxies:Coma, A1367, Virgo, A262 and Cancer, and in the bridge between Coma andA1367 in the ``Great Wall". The optically selected (mpg≤16.0) sample is representative of all Hubble types, from E to Irr+BCD,except dE and of significantly different environments, spanning fromisolated regions to rich clusters of galaxies. We model the surfacebrightness profiles with a de Vaucouleurs r1/4 law (dV), withan exponential disk law (E), or with a combination of the two (B+D).From the fitted quantities we derive the H band effective surfacebrightness (μe) and radius (re) of each component, theasymptotic magnitude HT and the light concentration indexC31. We find that: i) Less than 50% of the Ellipticalgalaxies have pure dV profiles. The majority of E to Sb galaxies is bestrepresented by a B+D profile. All Scd to BCD galaxies have pureexponential profiles. ii) The type of decomposition is a strong functionof the total H band luminosity (mass), independent of the Hubbleclassification: the fraction of pure exponential decompositionsdecreases with increasing luminosity, that of B+D increases withluminosity. Pure dV profiles are absent in the low luminosity rangeLH<1010 L\odot and become dominantabove 1011 L\odot . Based on observations taken atTIRGO, Gornergrat, Switzerland (operated by CAISMI-CNR, Arcetri,Firenze, Italy) and at the Calar Alto Observatory (operated by theMax-Planck-Institut für Astronomie (Heidelberg) jointly with theSpanish National Commission for Astronomy). Table 2 and Figs. 2, 3, 4are available in their entirety only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| 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).
| Galaxy Alignments in the Pisces-Perseus Supercluster Revisited
A search for preferential galaxy alignments in the Pisces-PerseusSupercluster (PPS) is made using the Minnesota Automated Plate ScannerPisces-Perseus Survey (MAPS-PP). The MAPS-PP is a catalog of ~1400galaxies with a (roughly) isophotal diameter greater than 30"constructed from digitized scans of the blue and red plates of thePalomar Observatory Sky Survey covering the PPS. This is the largestsample of galaxies applied to a search of galaxy alignments in thissupercluster, and it has been used in combination with previouslypublished redshifts to construct the deepest PPS galaxy luminosityfunction to date. While previous studies have relied extensively oncatalogs with visually estimated parameters for both sample selectionand determination of galaxy orientation, the MAPS-PP uses selectioncriteria and measurements that are entirely machine and computer based.Therefore, it is not susceptible to some of the biases, such as thediameter inclination effect, known to exist in some other galaxycatalogs. The presence of anisotropic galaxy distributions is determinedby use of the Kuiper statistic, a robust alternative to the chi^2statistic more traditionally used in these studies. Three statisticallysignificant anisotropic distributions are observed. The reddest galaxiesare observed to be oriented preferentially perpendicular to the locallarge-scale structure. The bluest galaxies near the supercluster planeare observed to have an anisotropic position angle distribution.Finally, a weak trend for the median position angle of color-selectedgalaxy subsamples to ``twist'' with increasing distance from the PPSplane is observed. These position angle distribution anisotropies areweak and are not consistent with any single primordial or modern-eragalaxy alignment mechanism, although a mixture of such mechanisms is notruled out.
| 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.
| 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
| 21 CM H1 Line Spectra of Galaxies in Nearby Clusters
A compilation of HI line fluxes, systemic velocities and line widths ispresented for \Ndet detected galaxies, mostly in the vicinities of 30nearby rich clusters out to a redshift of z ~ .04, specifically for usein applications of the Tully-Fisher distance method. New 21 cm HI lineprofiles have been obtained for ~ 500 galaxies in 27 Abell clustersvisible from Arecibo. Upper limits are also presented for \Nnod galaxiesfor which HI emission was not detected. In order to provide ahomogeneous line width determination optimized for Tully-Fisher studies,these new data are supplemented by the reanalysis of previouslypublished spectra obtained both at Arecibo and Green Bank that areavailable in a digital archive. Corrections for instrumental broadening,smoothing, signal-to-noise and profile shape are applied, and anestimate of the error on the width is given. When corrected forturbulent broadening and viewing angle, the corrected velocity widthspresented here will provide the appropriate line width parameter neededto derive distances via the Tully-Fisher relation.
| Photoelectric UBV Photometry of Galaxies in the Clusters Pegasus I, Pegasus II, Abell 262, Abell 1367, and Abell 2197-9
This paper presents photoelectric UBV multiaperture photometry of 144galaxies, 139 of which are associated with six nearby bright clusters.The observations were made at the McDonald Observatory from 1986September to 1987 November and were part of the production of the ThirdReference Catalogue of Bright Galaxies (RC3). The observations were usedto compute total magnitudes and color indices published in RC3. Theobservations can also be used to calibrate CCD images.
| 1.65 μm (H-band) surface photometry of disk galaxies. I. Observations of 158 galaxies with the Calar Alto 2.2 M telescope.
Near Infrared (H-band) surface photometry of 158 (mostly) disk galaxiesbelonging to the Coma Supercluster and to the A262 and Cancer clusterswas obtained using the 256^2^ NICMOS3 array MAGIC attached to the 2.2mCalar Alto telescope. Magnitudes and diameters within the21.5mag/arcsec^2^ isophote, concentration indices and total H magnitudesare derived.
| 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.
| Arm structure in normal spiral galaxies, 1: Multivariate data for 492 galaxies
Multivariate data have been collected as part of an effort to develop anew classification system for spiral galaxies, one which is notnecessarily based on subjective morphological properties. A sample of492 moderately bright northern Sa and Sc spirals was chosen for futurestatistical analysis. New observations were made at 20 and 21 cm; thelatter data are described in detail here. Infrared Astronomy Satellite(IRAS) fluxes were obtained from archival data. Finally, new estimatesof arm pattern radomness and of local environmental harshness werecompiled for most sample objects.
| A survey of the Pisces-Perseus supercluster. V - The declination strip +33.5 deg to +39.5 deg and the main supercluster ridge
Measurements of 544 radial velocities, 229 optical and 315 in the 21 cmH I line, are presented for galaxies, mostly in the declination stripbetween +33.5 and +39.5 deg in the region of the Pisces-Perseussupercluster. These are combined with other available data toinvestigate the linear structure identified as the main superclusterridge. The main ridge of the supercluster extends at least 50/h Mpcbefore it disappears into the zone of avoidance east of Perseus.Confinement both on the plane of the sky and in the velocity dimensionimply an axial ratio of greater than 10:1 and an inclination withrespect to the plane of the sky of less than about 12 degrees. Therelative proximity, low inclination to the plane of the sky, and highcontrast relative to the foreground and background, help to make thePisces-Perseus filament one of the most prominent features in theextragalactic sky on large scales.
| Angular Momentum in Binary Spiral Galaxies
In order to investigate the relative orientations of spiral galaxies inpairs, the distribution of the angle between the spin-vectors for a newsample of 40 binary spiral galaxies is determined. From thisdistribution it is found, contrary to an earlier result obtained byHelou (1984), that there is no indication of a correlation between theorientations of spiral galaxies in pairs. Also the distributions of therelative position angles for a sample of pairs are determined. The datadisagree with a simple model for isolated pairs based on tidal torques.A division of the sample into isolated and less-isolated pairs suggeststhat this disagreement is due to insufficient dynamical isolation duringgalaxy formation. The magnitude of the orbital angular momentum iscompared with that of the internal angular momentum of the galaxies forour sample as a whole. We find that the orbital angular momentum istypically 4 times larger than the internal angular momentum. This isinterpreted as an indication that the pairs in this sample were notdynamically isolated at the time they formed and that this is the reasonwhy no correlation between the spin-vectors is observed. We suggest thatpairs for which the spin- vectors were correlated had low orbitalangular momentum and have merged. Consequently, studying the relativeorientation of the spin-vectors in present day binary spiral galaxieswill not give strong constraints on the models for the origin ofgalactic angular momentum.
| Velocity differences in binary galaxies. I - Suggestions for a nonmonotonic, two-component distribution
A compilation of published high-precision velocities for 107 isolatedgalaxies is presented and used to obtain the distribution function oftheir velocity differences. The distribution shows a peak at the zerodifference as expected, but it also exhibits a preference for valuesnear 72 km/2. The distribution function declines smoothly beyond about72 km/s, with no significant peaks at multiples of 72 km/s, as claimedby Tifft (1977, 1980, 1982). It is argued that criteria for selectionprocedures on binary galaxy samples which are defined on the basis oftoo narrow a projected separation in the sky can produce a nonmonotonicdistribution if the orbits are eccentric. Such orbits can produce astrong secondary peak only if the level of incompleteness inbinary-galaxy samples is quite high, suggesting that the presentstatistical estimates of the masses of binary galaxies should bereevaluated.
| Multifrequency windows on spiral galaxies. II - The A262 and Cancer clusters
New photometrical data (U,B,V and H bands) are presented for about 100spiral galaxies in the A262 and Cancer clusters. The data are used tostudy the dependence of radio continuum to H band and FIR to H bandratios on the color index U - B, taken as an indicator of the starformation history in galaxy disks. Both parameters are found to increasein bluer galaxies, in agreement with the results obtained for otherclusters or field galaxies. The radio continuum activity of spiralgalaxies in the Cancer cluster is not enhanced like in other clusterspirals. A study of the reliability of CCD surface photometry isreported, based on the comparison of two sets of observations obtainedwith different telescopes.
| Kinematical observations of ordinary spiral galaxies - A bibliographical compilation
Data extracted from 280 papers reporting observations of the kinematicsof 245 nonbarred spiral galaxies are presented. Information is providedon the type of observations (instruments, spectral lines used, etc.) andthe derived geometrical and kinematical parameters of the galaxies(major axis position angle, inclination, heliocentric systemic velocity,maximum extension of the kinematical measurements, etc.). In addition,whenever possible, a 'mean' rotation curve has been considered, fromwhich the maximum rotational velocity of the galaxy and a parameterdescribing the essential shape of the rotation curve within r25 havebeen derived. Histograms illustrating the distribution of morphologicaltypes, inclinations, extensions of the kinematical measurements, andmaximum rotational velocities account for the statistical properties ofthis sample of spiral galaxies.
| HI observations of galaxies in nearby Zwicky clusters
The results of a long term project of H I observations of galaxieswithin the boundaries of nearby Zwicky clusters are presented. Thedetection rate is rather low (233 out of 618, i.e., 38 percent) ascompared to other surveys carried out recently. Most of the radialvelocities of the detected galaxies are new determinations. The largespread in radial velocities for many of these clusters is a strongindication for the presence of several foreground and/or backgroundgalaxies.
| Quantization of redshift differences in isolated galaxy pairs
Improved 21 cm data on isolated galaxy pairs are presented whicheliminate questions of inhomogeneity in the data on such pairs andreduce observational error to below 5 km/s. Quantization is sharpened,and the 'zero' peak is shown to be displaced from zero to a locationnear 24 km/s. An exclusion principle is suggested whereby identicalredshifts are forbidden in limited volumes. The radio data and data fromSchweizer (1987) are combined with the best optical data on closeKarachentsev pairs to provide a cumulative sample of 84 of the bestdifferentials now available. New 21 cm observations are used to test forthe presence of small differentials in very wide pairs, and thedeficiency near zero is found to continue to very wide spacings. A lossof wide pairs by selection bias cannot produce the observed zerodeficiency. A new test using pairs selected from the Fisher-Tullycatalog is used to demonstrate quantization properties of thirdcomponents associated with possible pairs.
| Far-infrared properties of cluster galaxies
Far-infrared properties are derived for a sample of over 200 galaxies inseven clusters: A262, Cancer, A1367, A1656 (Coma), A2147, A2151(Hercules), and Pegasus. The IR-selected sample consists almost entirelyof IR normal galaxies, with Log of L(FIR) = 9.79 solar luminosities, Logof L(FIR)/L(B) = 0.79, and Log of S(100 microns)/S(60 microns) = 0.42.None of the sample galaxies has Log of L(FIR) greater than 11.0 solarluminosities, and only one has a FIR-to-blue luminosity ratio greaterthan 10. No significant differences are found in the FIR properties ofHI-deficient and HI-normal cluster galaxies.
| Dark matter associated with binary galaxies
Sixteen pairs of galaxies have been observed previously using theWesterbork Synthesis Radio Telescope (WSRT) in the 21-cm line of neuralhydrogen. In this paper the derived kinematical parameters are used tostudy the possible presence of dark matter. For each pair informationwas obtained about the internal kinematics of each member and about therelative motion of the members with respect to each other. The combinedmass of both member galaxies individually is compared to the minimumtotal mass following from the relative motion. Care is taken to estimatethe effects of the well defined criteria applied to select the sample.In about one half of the observed pairs there is direct evidence of darkmatter, and from statistical arguments the data indicate an averageratio dark matter/visible matter of 3. It appears that even among widelyseparated pairs a point mass model is not adequate. The observations canbe fitted to a logarithmic potential characterized by an extended matterdistribution enveloping the galaxies.
| Alignments of galaxies in the Perseus supercluster
The relative orientations of the galaxies belonging to the Perseussupercluster are investigated. The result is a lack of alignment in anypreferred direction of the supercluster galaxies (ellipticals, spiralsand both), except in a selected region of the supercluster, whosesignificance is low. Moreover no evidence of anisotropy in the relativeorientations of neighboring galaxies has been found.
| The nuclear activity of interacting galaxies
A search for active galactic nuclei among interacting galaxies isreported. A sample of 167 systems of interacting and asymmetric galaxieswas observed spectrophotometrically in the spectral range 4700-7100 A.The results are compared with a sample of isolated galaxies. It is foundthat (1) there are no Seyfert nuclei in elliptical or dwarf irregulargalaxies of the sample; (2) there is an excess of Seyfert nuclei amonginteracting spirals, but it is only at the 90 percent confidence level;(3) this excess becomes statistically significant (98 percent) when onlystrongly interacting spirals are included (four new Seyfert nuclei arepresented); (4) in the subgroup of galaxies with extreme tidaldistortions, no Seyfert nuclei were found.
| Gas deficiency in cluster galaxies - A comparison of nine clusters
The available 21 cm line data in the literature for galaxies in nineclusters is combined with new high-sensitivity observations of 51galaxies in five of the nine clusters in order to test fordiscriminating circumstances between those clusters which show H Ideficiency among their spiral population and those which do not. An H Ideficiency for the complete cluster sample is derived employing acomparison sample of galaxies chosen from the Catalog of IsolatedGalaxies. The deficiency and its radial dependence is summarized foreach cluster and a composite. A comparison of the environments indifferent clusters leads to the conclusion that the occurrence of H Ideficiency is correlated with the presence of a hot X-ray intraclustermedium, and that an ongoing interaction process is active through thecores of X-ray clusters.
| Supplement to the detailed bibliography on the surface photometry of galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...60..517P&db_key=AST
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