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Low-Luminosity Active Galaxies and Their Central Black Holes
Central black hole masses for 117 spiral galaxies representingmorphological stages S0/a through Sc and taken from the largespectroscopic survey of Ho et al. are derived using Ks-banddata from the Two Micron All Sky Survey. Black hole masses are foundusing a calibrated black hole-Ks bulge luminosity relation,while bulge luminosities are measured by means of a two-dimensionalbulge-disk decomposition routine. The black hole masses are correlatedagainst a variety of parameters representing properties of the nucleusand host galaxy. Nuclear properties such as line width (FWHM [N II]), aswell as emission-line ratios (e.g., [O III]/Hβ, [O I]/Hα, [NII]/Hα, and [S II]/Hα), show a very high degree ofcorrelation with black hole mass. The excellent correlation with linewidth supports the view that the emission-line gas is in virialequilibrium with either the black hole or bulge potential. The very goodemission-line ratio correlations may indicate a change in ionizingcontinuum shape with black hole mass in the sense that more massiveblack holes generate harder spectra. Apart from theinclination-corrected rotational velocity, no excellent correlations arefound between black hole mass and host galaxy properties. Significantdifferences are found between the distributions of black hole masses inearly-, mid-, and late-type spiral galaxies (subsamples A, B, and C) inthe sense that early-type galaxies have preferentially larger centralblack holes, consistent with observations that Seyfert galaxies arefound preferentially in early-type systems. The line width distributionsshow a marked difference among subsamples A, B, and C in the sense thatearlier type galaxies have larger line widths. There are also cleardifferences in line ratios between subsamples A+B and C that likely arerelated to the level of ionization in the gas. Finally, aKs-band Simien & de Vaucouleurs diagram shows excellentagreement with the original B-band relation, although there is a largedispersion at a given morphological stage.
| Classifications of the Host Galaxies of Supernovae, Set III
A homogeneous sample comprising host galaxies of 604 recent supernovae,including 212 objects discovered primarily in 2003 and 2004, has beenclassified on the David Dunlap Observatory system. Most SN 1991bg-likeSNe Ia occur in E and E/Sa galaxies, whereas the majority of SN1991T-like SNe Ia occur in intermediate-type galaxies. This differenceis significant at the 99.9% level. As expected, all types of SNe II arerare in early-type galaxies, whereas normal SNe Ia occur in all Hubbletypes. This difference is significant at the 99.99% level. A smallnumber of SNe II in E galaxies might be due to galaxy classificationerrors or to a small young-population component in these mainly oldobjects. No significant difference is found between the distributionsover the Hubble type of SNe Ibc and SNe II. This confirms that both ofthese types of objects have similar (massive) progenitors. The presentdata show that in order to understand the dependence of supernova typeon host-galaxy population, it is more important to obtain accuratemorphological classifications than it is to increase the size of thedata sample.
| GHASP: an Hα kinematic survey of spiral and irregular galaxies - IV. 44 new velocity fields. Extension, shape and asymmetry of Hα rotation curves
We present Fabry-Perot observations obtained in the frame of the GHASPsurvey (Gassendi HAlpha survey of SPirals). We have derived the Hαmap, the velocity field and the rotation curve for a new set of 44galaxies. The data presented in this paper are combined with the datapublished in the three previous papers providing a total number of 85 ofthe 96 galaxies observed up to now. This sample of kinematical data hasbeen divided into two groups: isolated (ISO) and softly interacting(SOFT) galaxies. In this paper, the extension of the Hα discs, theshape of the rotation curves, the kinematical asymmetry and theTully-Fisher relation have been investigated for both ISO and SOFTgalaxies. The Hα extension is roughly proportional toR25 for ISO as well as for SOFT galaxies. The smallestextensions of the ionized disc are found for ISO galaxies. The innerslope of the rotation curves is found to be correlated with the centralconcentration of light more clearly than with the type or thekinematical asymmetry, for ISO as well as for SOFT galaxies. The outerslope of the rotation curves increases with the type and with thekinematical asymmetry for ISO galaxies but shows no special trend forSOFT galaxies. No decreasing rotation curve is found for SOFT galaxies.The asymmetry of the rotation curves is correlated with themorphological type, the luminosity, the (B-V) colour and the maximalrotational velocity of galaxies. Our results show that the brightest,the most massive and the reddest galaxies, which are fast rotators, arethe least asymmetric, meaning that they are the most efficient withwhich to average the mass distribution on the whole disc. Asymmetry inthe rotation curves seems to be linked with local star formation,betraying disturbances of the gravitational potential. The Tully-Fisherrelation has a smaller slope for ISO than for SOFT galaxies.
| Supernova 2004ez in NGC 3430
IAUC 8419 available at Central Bureau for Astronomical Telegrams.
| An IRAS High Resolution Image Restoration (HIRES) Atlas of All Interacting Galaxies in the IRAS Revised Bright Galaxy Sample
The importance of far-infrared observations for our understanding ofextreme activity in interacting and merging galaxies has beenillustrated by many studies. Even though two decades have passed sinceits launch, the most complete all-sky survey to date from which far-IRselected galaxy samples can be chosen is still that of the InfraredAstronomical Satellite (IRAS). However, the spatial resolution of theIRAS all-sky survey is insufficient to resolve the emission fromindividual galaxies in most interacting galaxy pairs, and hence previousstudies of their far-IR properties have had to concentrate either onglobal system properties or on the properties of very widely separatedand weakly interacting pairs. Using the HIRES image reconstructiontechnique, it is possible to achieve a spatial resolution ranging from30" to 1.5m (depending on wavelength and detector coverage), whichis a fourfold improvement over the normal resolution of IRAS. This issufficient to resolve the far-IR emission from the individual galaxiesin many interacting systems detected by IRAS, which is very importantfor meaningful comparisons with single, isolated galaxies. We presenthigh-resolution 12, 25, 60, and 100 μm images of 106 interactinggalaxy systems contained in the IRAS Revised Bright Galaxy Sample (RBGS,Sanders et al.), a complete sample of all galaxies having a 60 μmflux density greater than 5.24 Jy. These systems were selected to haveat least two distinguishable galaxies separated by less than threeaverage galactic diameters, and thus we have excluded very widelyseparated systems and very advanced mergers. Additionally, some systemshave been included that are more than three galactic diameters apart,yet have separations less than 4' and are thus likely to suffer fromconfusion in the RBGS. The new complete survey has the same propertiesas the prototype survey of Surace et al. We find no increased tendencyfor infrared-bright galaxies to be associated with other infrared-brightgalaxies among the widely separated pairs studied here. We find smallenhancements in far-IR activity in multiple galaxy systems relative toRBGS noninteracting galaxies with the same blue luminosity distribution.We also find no differences in infrared activity (as measured byinfrared color and luminosity) between late- and early-type spiralgalaxies.
| Inner-truncated Disks in Galaxies
We present an analysis of the disk brightness profiles of 218 spiral andlenticular galaxies. At least 28% of disk galaxies exhibit innertruncations in these profiles. There are no significant trends oftruncation incidence with Hubble type, but the incidence among barredsystems is 49%, more than 4 times that for nonbarred galaxies. However,not all barred systems have inner truncations, and not allinner-truncated systems are currently barred. Truncations represent areal dearth of disk stars in the inner regions and are not an artifactof our selection or fitting procedures nor the result of obscuration bydust. Disk surface brightness profiles in the outer regions are wellrepresented by simple exponentials for both truncated and nontruncateddisks. However, truncated and nontruncated systems have systematicallydifferent slopes and central surface brightness parameters for theirdisk brightness distributions. Truncation radii do not appear tocorrelate well with the sizes or brightnesses of the bulges. Thissuggests that the low angular momentum material apparently missing fromthe inner disk was not simply consumed in forming the bulge population.Disk parameters and the statistics of bar orientations in our sampleindicate that the missing stars of the inner disk have not simply beenredistributed azimuthally into bar structures. The sharpness of thebrightness truncations and their locations with respect to othergalactic structures suggest that resonances associated with diskkinematics, or tidal interactions with the mass of bulge stars, might beresponsible for this phenomenon.
| 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
| Disk-bulge decompositions of spiral galaxies in UBVRI
A sample of 26 bright spiral galaxies (Btot < 12.7) withlow to medium inclination and without a bar was observed with UBVRIfilters. The CAFOS focal reducer camera at the Calar Alto 2.2 mtelescope was used. The surface-brightness distributions were fittedusing a 2-dimensional algorithm with corresponding functions for thedisk- and bulge-structure. For the disks an exponential function wasused, for the bulges a Sérsic Rβ law, was appliedwith the concentration parameter β = 1/n as another fit variable.Correlations of the resulting structural parameters of disks and bulgesin UBVRI are investigated, giving clues to the formation history of thebulges.We confirm that the large and bright bulges of early-type spirals aresimilar to elliptical galaxies. They were probably formed prior to thedisks in a monolithic collapse or via early mergers. Late-type spiralshave tiny and faint bulges with disk-like profiles. These bulges wereprobably formed after the disk in secular evolution processes, e.g. froma disk instability. The comparison of the color indices of correspondingspirals and bulges with population synthesis computations support aboveformation scenarios.Tables 2-4 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/415/63
| Star Formation Across the Taffy Bridge: UGC 12914/15
We present Berkeley-Illinois-Maryland Association (BIMA) two-fieldmosaic CO (1-0) images of the Taffy galaxies (UGC 12914/15), which showthe distinct taffy-like radio continuum emission bridging the two spiraldisks. Large amounts of molecular gas (1.4×1010Msolar, using the standard Galactic CO-to-H2conversion applicable to Galactic disk giant molecular clouds) wereclearly detected throughout the taffy bridge between the two galaxies,which, as in the more extreme case of H I, presumably results from ahead-on collision between the two galaxies. The highest CO concentrationbetween the two galaxies corresponds to the Hα source in the taffybridge near the intruder galaxy UGC 12915. This H II region is alsoassociated with the strongest source of radio continuum in the bridgeand shows both morphological and kinematic connections to UGC 12915. Theoverall CO distribution of the entire system agrees well with that ofthe radio continuum emission, particularly in the taffy bridge. Thisargues for the star formation origin of a significant portion of theradio continuum emission. Compared with the H I morphology andkinematics, which are strongly distorted owing to the high-speedcollision, CO better defines the orbital geometry and impact parameterof the interaction, as well as the disk properties (e.g., rotation,orientation) of the progenitor galaxies. Based on the 20 cm-to-CO ratiomaps, we conclude that the starburst sites are primarily located in UGC12915 and the Hα source in the bridge and show that the moleculargas in the taffy bridge is forming into stars with star formationefficiency comparable to that of the target galaxy UGC 12914 and similarto that in the Galactic disk.
| A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| A Search for Active Galactic Nuclei in Sc Galaxies with H II Spectra
We have searched for nuclear radio emission from a statisticallycomplete sample of 40 Sc galaxies within 30 Mpc that are opticallyclassified as star-forming objects, in order to determine whether weakactive galactic nuclei might be present. Only three nuclear radiosources were detected, in NGC 864, NGC 4123, and NGC 4535. Thesegalaxies have peak 6 cm radio powers of ~1020 WHz-1 at arcsecond resolution, while upper limits of thenondetected galaxies typically range from 1018.4 to1020 W Hz-1. The three nuclear radio sources areall resolved and appear to have diffuse morphologies, with linear sizesof ~300 pc. This strongly indicates that circumnuclear star formationhas been detected in these three H II galaxies. Comparisons withprevious 20 cm Very Large Array (VLA) results for the detected galaxiesshow that the extended nuclear radio emission has a flat spectrum in twoobjects and is almost certainly generated by thermal emission from gasionized by young stars in the centers of those galaxies. The 6 cm radiopowers are comparable to predictions for thermal emission that are basedon the nuclear Hα luminosities and imply nuclear star formationrates of 0.08-0.8 Msolar yr-1, while thelow-resolution NRAO VLA Sky Survey implies galaxy-wide star formationrates of 0.3-1.0 Msolar yr-1 in stars above 5Msolar. In a few of the undetected galaxies, the upper limitsto the radio power are lower than predicted from the Hαluminosity, possibly because of overresolution of central star-formingregions. Although the presence of active nuclei powered by massive blackholes cannot be definitively ruled out, the present results suggest thatthey are likely to be rare in these late-type galaxies with H IIspectra.
| GHASP: A 3-D Survey of Spiral and Irregular Galaxies at Hα
Not Available
| Bar Galaxies and Their Environments
The prints of the Palomar Sky Survey, luminosity classifications, andradial velocities were used to assign all northern Shapley-Ames galaxiesto either (1) field, (2) group, or (3) cluster environments. Thisinformation for 930 galaxies shows no evidence for a dependence of barfrequency on galaxy environment. This suggests that the formation of abar in a disk galaxy is mainly determined by the properties of theparent galaxy, rather than by the characteristics of its environment.
| The UZC-SSRS2 Group Catalog
We apply a friends-of-friends algorithm to the combined Updated ZwickyCatalog and Southern Sky Redshift Survey to construct a catalog of 1168groups of galaxies; 411 of these groups have five or more members withinthe redshift survey. The group catalog covers 4.69 sr, and all groupsexceed the number density contrast threshold, δρ/ρ=80. Wedemonstrate that the groups catalog is homogeneous across the twounderlying redshift surveys; the catalog of groups and their membersthus provides a basis for other statistical studies of the large-scaledistribution of groups and their physical properties. The medianphysical properties of the groups are similar to those for groupsderived from independent surveys, including the ESO Key Programme andthe Las Campanas Redshift Survey. We include tables of groups and theirmembers.
| Compact groups in the UZC galaxy sample
Applying an automatic neighbour search algorithm to the 3D UZC galaxycatalogue (Falco et al. \cite{Falco}) we have identified 291 compactgroups (CGs) with radial velocity between 1000 and 10 000 kms-1. The sample is analysed to investigate whether Tripletsdisplay kinematical and morphological characteristics similar to higherorder CGs (Multiplets). It is found that Triplets constitute lowvelocity dispersion structures, have a gas-rich galaxy population andare typically retrieved in sparse environments. Conversely Multipletsshow higher velocity dispersion, include few gas-rich members and aregenerally embedded structures. Evidence hence emerges indicating thatTriplets and Multiplets, though sharing a common scale, correspond todifferent galaxy systems. Triplets are typically field structures whilstMultiplets are mainly subclumps (either temporarily projected orcollapsing) within larger structures. Simulations show that selectioneffects can only partially account for differences, but significantcontamination of Triplets by field galaxy interlopers could eventuallyinduce the observed dependences on multiplicity. Tables 1 and 2 are onlyavailable in electronic at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/391/35
| GHASP: An Hα kinematic survey of spiral and irregular galaxies. I. Velocity fields and rotation curves of 23 galaxies
GHASP (Gassendi Hα survey of SPirals) is a survey of Hαvelocities in spiral and irregular galaxies. The observations began in1998, with a scanning Fabry-Perot and a focal reducer attached at theCassegrain focus of the 1.93 m telescope at the Observatoire deHaute-Provence. This paper presents the Hα maps, the 2D velocityfields and the rotation curves obtained for a set of 23 galaxiesobserved in October 1998 and April 1999. Most of them have already beenobserved in HI in the frame of the WHISP survey led at Westerbork, forwhich GHASP brings an interesting complement. The aim is to provide areference sample of 2D velocity fields for about 200 nearby spiralgalaxies at Hα wavelength. Based on observations collected at theObservatoire de Haute de Provence. All the figures are only available inelectronic form at http://www.edpsciences.org
| 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.
| HI observations of loose galaxy groups. I. Data and global properties
At Nançay, 21-cm H I line observations were made of 15spiral-dominated loose groups of galaxies, divided into two samples: an``interacting'' sample containing at least one pair of interactinggalaxies, and a ``control'' sample having no optical evidence ofinteractions or morphological disturbances among the group members. Theinteracting sample consists of 62 galaxies representing 9 differentgroups, and the control sample contains 40 galaxies representing 6groups. Of the 91 galaxy and galaxy pairs observed, 74 were detected,while upper limits were placed on the remaining 17 objects. Thesehomogeneous H I data, which will be used in future analyses, providecomparative information on the H I content of groups and serve as aprobe of the vicinity of the target spirals for H I clouds or very lowsurface brightness gas-rich galaxies.
| Surface photometry of spiral galaxies in NIR: Structural parameters of disks and bulges
A sample of 40 bright spiral galaxies (BT < 12) with lowinclination and without bar was observed with JHK filters. For thispurpose the MAGIC NICMOS3 camera at the 2.2 m telescope of the CalarAlto observatory, Spain was used. With a newly developed 2-dimensionalalgorithm the distribution of the surface brightness was fittedsimultaneously by corresponding functions for the disk- andbulge-structure. While the disk was fitted with an exponential function,the bulge profile was fitted with a generalized de VaucouleursRbeta law, with the concentration parameter beta = 1/n as afurther fit variable. The correlation of the resulting structuralparameters of disks and bulges lead to some interesting relations: 1.The use of a variable exponent beta is necessary for a realisticdescription of the bulge structure; 2. Disks and bulges show similarcorrelations between effective radius, effective surface brightness andluminosity; 3. They populate a common strip in the fundamental plane; 4.From the correlations between beta and Hubble type some conclusionsabout the formation and evolution of spiral galaxies can be drawn.
| The formation of galaxy bulges: Spectrophotometric constraints
We have measured Mg2, Fe 5270 and Fe 5335 spectrophotometricindices (LICK system) in the bulge of 89 galaxies, mostly spirals fromthe Héraudeau (\cite{her96}) sample. The indices are reduced to anull velocity dispersion and normalized to an aperture of 0.2h-1 kpc. The mean errors are 0.009 mag on Mg2, and0.3 Å on the iron indices. These measurements almost double theamount of similar data already available on spiral galaxies. Our dataconfirm the existence of the relation between Mg2, andsigma0, the central stellar velocity dispersion; we find aneven tighter relation between Mg2, andVmrot, the maximum rotational velocity of thegalaxy, deduced from HI observations. For the most massive bulges, thesecorrelations may be interpreted as a mass-metallicity relation. However,the presence of young stellar populations, traced by the detection of[OIII] lambda 5007 Å, emission, provides clear evidence that ageeffects do play a role. Since the contribution of the young populationis anti-correlated to the mass of the galaxy, it continues theMg2, vs. sigma0 , relation toward thelow-sigma0, region and globally increases its slope. We alsopresent evidence for a new positive correlation between Fe indices andsigma0, and for a significant correlation between theline-strength indices and the total or disk luminosity. We propose tomodel the whole sequence of bulges within the folowing framework: bulgesare composed of a primary population formed prior to the disk, duringthe initial collapse, and of a secondary population formed during itsevolution. The whole family of bulges can be classified into threeclasses: (A) the bulges dominated by young populations are generallysmall, have ionized gas, low velocity dispersion and low line strengths;(B) the bulges dominated by the primary population lie along themass-metallicity sequence defined for elliptical galaxies; and (C) thebulges where the secondary population is significant are lessMg-over-abundant than (B)-type bulges and deviate from theMg2, vs. sigma0, relation of elliptical galaxies.Based on observations collected at the Observatoire de Haute-Provence.Table 3 is presented in electronic form only at the CDS. Tables 1 and 2are also available form at the CDS, Strasbourg, via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/366/68
| The 1.0 Megaparsec Galaxy Pair Sample in Low-Density Regions
Using complete redshift catalogs, we have compiled a list of galaxypairs based solely on a pair's projected separation, rp, andvelocity difference, ΔV. We have made high-velocity precision H Iobservations of each galaxy in the sample and have reported these in theliterature. Due to the nature of the redshift catalogs, we are able toquantitatively evaluate the effects of isolation and number density ofsurrounding galaxies on each pair in the sample. For the close galaxypairs (rp<100 kpc), the degree of isolation (a measure ofthe number of near neighbors) has little effect on the median ΔV.This median is about 55 km s-1 for the 25 close pairs (ifmedium-density close pairs are omitted ΔV is even smaller, but thedifference is not statistically significant). The effect of isolation isstrong for the entire sample of galaxy pairs with separations as largeas 1.0 Mpc. For these larger separation pairs, relaxation of strictisolation requirements introduces small groups into the sample, whichdramatically increases the median ΔV. We find little evidence ofan increase in the median ΔV with decreasing rp, norwith increasing total luminosity. For our isolated pairs in low-densityregions, the overall median ΔV is only 30 km s-1. Forsimilar separations and isolation criteria, galaxy satellites withlarger luminosity ratios (i.e., less dynamical friction) in higherdensity regions have ΔV approximately twice as large. Weconjecture that our orbits are highly eccentric, so that the indirecteffect of dynamical friction leads to predominantly small ΔV.However, the halos of our galaxies may also be of low density (althoughhighly extended).
| 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.
| 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.
| Investigation of Barred Galaxies. V. Surroundings of SB and SA Galaxies
Not Available
| Groups of galaxies. III. Some empirical characteristics.
Not Available
| Bulge-Disk Decomposition of 659 Spiral and Lenticular Galaxy Brightness Profiles
We present one of the largest homogeneous sets of spiral and lenticulargalaxy brightness profile decompositions completed to date. The 659galaxies in our sample have been fitted with a de Vaucouleurs law forthe bulge component and an inner-truncated exponential for the diskcomponent. Of the 659 galaxies in the sample, 620 were successfullyfitted with the chosen fitting functions. The fits are generally welldefined, with more than 90% having rms deviations from the observedprofile of less than 0.35 mag. We find no correlations of fittingquality, as measured by these rms residuals, with either morphologicaltype or inclination. Similarly, the estimated errors of the fittedcoefficients show no significant trends with type or inclination. Thesedecompositions form a useful basis for the study of the lightdistributions of spiral and lenticular galaxies. The object base issufficiently large that well-defined samples of galaxies can be selectedfrom it.
| 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
| A Search for ``Dwarf'' Seyfert Nuclei. III. Spectroscopic Parameters and Properties of the Host Galaxies
We have completed an optical spectroscopic survey of the nuclear regions(r <~ 200 pc) of a large sample of nearby galaxies. Although the mainobjectives of the survey are to search for low-luminosity activegalactic nuclei and to quantify their luminosity function, the databasecan be used for a variety of other purposes. This paper presentsmeasurements of the spectroscopic parameters for the 418 emission-linenuclei, along with a compilation of the global properties of all 486galaxies in the survey. Stellar absorption generally poses a seriousobstacle to obtaining accurate measurement of emission lines in nearbygalactic nuclei. We describe a procedure for removing the starlight fromthe observed spectra in an efficient and objective manner. The mainparameters of the emission lines (intensity ratios, fluxes, profilewidths, and equivalent widths) are measured and tabulated, as areseveral stellar absorption-line and continuum indices useful forstudying the stellar population. Using standard nebular diagnostics, wedetermine the probable ionization mechanisms of the emission-lineobjects. The resulting spectral classifications provide extensiveinformation on the demographics of emission-line nuclei in the nearbyregions of the universe. This new catalog contains over 200 objectsshowing spectroscopic evidence for recent star formation and an equallylarge number of active galactic nuclei, including 46 that show broad Halpha emission. These samples will serve as the basis of future studiesof nuclear activity in nearby galaxies.
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