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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
| 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
| 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.
| 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.
| An Einstein X-Ray Survey of Optically Selected Galaxies. I. Data
We present the results of a complete Einstein imaging proportionalcounter X-ray survey of optically selected galaxies from theShapley-Ames Catalog, the Uppsala General Catalogue, and the EuropeanSouthern Observatory Catalog. Well-defined optical criteria are used toselect the galaxies, and X-ray fluxes are measured at the opticallydefined positions. The result is a comprehensive list of X-ray detectionand upper limit measurements for 1018 galaxies. Of these, 827 haveeither independent distance estimates or radial velocities. Associatedoptical, redshift, and distance data have been assembled for thesegalaxies, and their distances come from a combination of directlypredicted distances and those predicted from the Faber-Burstein GreatAttractor/Virgocentric infall model. The accuracy of the X-ray fluxeshas been checked in three different ways; all are consistent with thederived X-ray fluxes being of <=0.1 dex accuracy. In particular,there is agreement with previously published X-ray fluxes for galaxiesin common with a 1991 study by Roberts et al. and a 1992 study byFabbiano et al. The data presented here will be used in further studiesto characterize the X-ray output of galaxies of various morphologicaltypes and thus to enable the determination of the major sourcescontributing to the X-ray emission from galaxies.
| Extended LY alpha -absorbing Halos around Nearby Galaxies
In order to establish the Lyα absorption cross section ofpresent-day galaxies, we have identified 38 galaxies with z = 0-0.08that lie within 40-500 h^-1^ kpc of the line of sight to a QSO observedwith the Faint Object Spectrograph aboard the Hubble Space Telescope(HST). Including three galaxies in the field of 3C 273 investigated byprevious authors, we find that nine of 41 galaxies have associatedLyα absorption. If the identified Lyα absorption systems aregenuinely associated with the galaxies, then the covering factor of gasaround galaxies remains roughly constant at ~40% between 100 and 300h^-1^ kpc. Beyond 300 h^-1^ kpc, the incidence of absorption dropssharply. We conclude that (1) nearby galaxies do not possessLyα-absorbing halos beyond 300 h^-1^ kpc in radius and (2) thecovering factor of present-day galaxies between 50 and 300 h^-1^ kpc is44% at an equivalent width limit of W >= 0.3 A. For the nine galaxieswith associated Lyα absorption lines, differences in the galaxiessystemic velocities and the velocity of the absorption line, {DELTA}v,range over +/- 300 km s^-1^, consistent with the distribution found atredshifts > 0.1 by Lanzetta et al. and Le Brun, Bergeron, &Boisse. Values of {DELTA}v spanning several hundred km s^-1^ areprobably real for some of the QSO-galaxy pairs, however, and do notsimply arise from errors in measuring cz_gal_ or cz_abs_. This suggeststhat the absorbing clouds are kinematically tied to the galaxy disks andthat the distribution of {DELTA}v may arise because of the effects ofgalaxy inclination. We find no evidence for a correlation betweenLyα equivalent width and galaxy line-of-sight separation, whichweakens the argument that the identified galaxies are directlyassociated with the Lyα lines. Also, we find that absorption doesnot arise only from bright galaxies, since there are several examples inwhich low-luminosity galaxies apparently cause absorption. Yet we showthat the absorbing halos around galaxies cannot be independent of galaxyluminosity because if all low- redshift galaxies were surrounded byextended halos, the number of Lyα absorption systems found in HSTspectra would be much larger than has recently been determined. Thisresult leads us to question whether the galaxies are actuallyresponsible for the Lyα absorption lines or whether theassociation in redshift is fortuitous. Our results support the picturesuggested by others that Lyα lines arise in filaments or sheetsthat connect and contain the overdense regions that galaxies inhabit.This conclusion, however, remains at odds with the results of Lanzettaet al., who find that Lyα systems are more intimately linked withgalaxies. It may be, therefore, that we are seeing an evolution of theway in which Ly& lines associate with galaxies over the last fewbillion years. We suggest that at least some of the Lyα cloudsthat are not associated with galaxies at z ~ 0.5 have been slowlymerging with galaxies over time, creating larger but less uniform gasdistributions around the galaxies we see today.
| 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.
| Blue spectropolarimetry of Seyfert 2 galaxies. 1: Analysis and basic results
Spectropolarimetry in the 3200-6200 A range was obtained on 50 Seyert 2galaxies. After careful subtraction of a template galaxy, the fractionsof the total flux due to starlight Fg and to the featurelesscontinuum Fc were estimated. All of the Seyfert 2 galaxieshave a nonstellar component to their spectrum. Polarization is notcorrelted with Fc which argues against the hypothesis thatall Seyfert 2s have highly polarized featureless continua which areunseen because of dilution by starlight. The nine Seyfert 2s withspectropolarimetrically identified hidden broad-line regions (BLRs) havethe mean value of Fg = 0.30 considerably less than theaverage of 0.70 found for the larger sample. This suggests that thespectropolarimetric method of identifying hidden BLRs in Seyfert 2s ismost sensitive to objects in which the polarization is less contaminatedby a large fraction of starlight. The spectopolarimetric data indicatesa few additional objects, Mrk 266SW and Mrk 573, which may containhidden BLRs, but they require further study at H-alpha.
| Less probable IRR II candidateas
The paper presents a list of 89 less probable Irr candidates in whichthe presence of dust is suspected. In a commentary to this list, theshape of the galaxies is described and their location in relation toneighboring background galaxies is noted.
| Markarian Galaxies and Stellar Formation Regions
Not Available
| A statistical study of the relationship between galaxy interactions and nuclear activity
Small-aperture near- and mid-infrared photometry of a complete sample ofinteracting galaxies has been obtained. Statistical comparison of thenuclear properties of these galaxies with samples of noninteractinggalaxies shows that signs of abnormal nuclear activity are much morecommon in interacting systems. In particular, a population of nucleiwith extremely luminous 10 micron emission is unique to the interactingsample. Roughly half of the interacting galaxies with nuclear 10 micronsources also exhibit evidence of extended 10 micron emission usingmeasurements from IRAS. The far-infrared luminosities of the interactingsample are also greater than those of representative selections ofnormal galaxies. The identification of extraluminous infrared emissionin a significant number of the surveyed galaxies suggests thatinteractions may in some way be associated with other high-luminosityphenomena such as Seyfert nuclei and QSOs.
| A survey of O II forbidden line emission in elliptical galaxies
A survey of elliptical galaxy spectra using image-tube spectrograms hasbeen carried out with the result that 40 percent of the galaxies havebeen found to contain ionized gas. Galaxies with intense nuclearemission also tend to have extended emission that appears to be confinedto a plane. Since there is a detectable velocity gradient for the gas inthose planes, the gas appears to be in a rotating disk.
| DDO photometry and metallic abundances of E and SO galaxies and globular clusters of the LMC and SMC
Metallicity of 8 E and SO galaxies as well as that of red globulars ofthe LMC and SMC were obtained by means of DDO integrated photometrycalibrated with galactic globular clusters (Bica and Pastoriza, 1983;hereafter referred to as Paper I). A correction was obtained in order toreduce the colors of the galaxies to zero redshift. The relationmetallicity vs M~ for the galaxies is analyzed (adding to our sample theobservations of McClure and Van den Bergh, 1968; and Faber, 1973a). Forthe Magellanic Clouds we found metallicity ranging from intermediate topoor
| The absorption-line strengths if elliptical and S0 galaxies.
Not Available
| The absorption-line strengths of elliptical and S0 galaxies
A subset of Faber's (1973) ten-color system is used to measureabsorption line strengths (LS) and colors of five S0 galaxies, twoellipticals, and three globular clusters. These observations arecombined with Faber's in order to analyze LS and color variations amongold stellar populations. The LS index (Mg)0 is found to beuseful for the study of old stellar populations. This index iscalibrated in terms of Fe/H (solar) from -2.2 to -0.5 on the basis ofglobular clusters and is extended to approximately 0.3 by using Mould's(1978) theoretical calculations. It is shown that most S0's,ellipticals, and globular clusters define a tight relationship in a plotof (Mg)0 vs. (45 - 67)0 and that the principalphysical parameter varying along this relationship is most plausibly theaverage metallicity of the stellar population. The S0's and ellipticalswith known or suspected young stellar components are found to deviatefrom this relationship, along lines termed bluing vectors.
| Statistical Analysis of Discrepant Redshift Associations. II. QSO-Galaxy and QSO-QSO Pairs
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&A....70...13M&db_key=AST
| Variations in Spectral-Energy Distributions and Absorption-Line Strengths among Elliptical Galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973ApJ...179..731F&db_key=AST
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