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Публикации по объекту
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
| Background galaxies as reddening probes throughout the Magellanic Clouds
We study the spectral properties in the range 3600 Å-6800 Åof the nuclear region of galaxies behind the Magellanic Clouds. Theradial velocities clarified the nature of the objects as backgroundgalaxies or extended objects belonging to the Clouds. For most galaxiesbehind the main bodies of the LMC and SMC, radial velocities weremeasured for the first time. In the present sample typical LMCbackground galaxies are nearby (4000 < V(km s-1) <6000), while SMC's are considerably more distant (10 000 < V(kms-1) < 20 000). We determine the reddening in each line ofsight by matching a reddening-free galaxy template with comparablestellar population. For the LMC main body we derive a combined Milky Wayand internal reddening value E(B-V)MW+i = 0.12 +/- 0.10,while for the SMC E(B-V)MW+i = 0.05 +/- 0.05. By subtractingMilky Way reddening values for galaxies projected onto the surroundingsof each Cloud, we estimate average internal reddening values DeltaE(B-V)i = 0.06 and 0.04, respectively for the main bodies ofthe LMC and SMC. The Clouds are optically thin, at least in thedirections of the studied background galaxies which are often difficultto be identified as such on ESO/SERC sky survey images. Nevertheless,more reddened zones may occur where it is difficult to identifygalaxies.
| 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.
| Box- and peanut-shaped bulges. I. Statistics
We present a classification for bulges of a complete sample of ~ 1350edge-on disk galaxies derived from the RC3 (Third Reference Catalogue ofBright Galaxies, de Vaucouleurs et al. \cite{rc3}). A visualclassification of the bulges using the Digitized Sky Survey (DSS) inthree types of b/p bulges or as an elliptical type is presented andsupported by CCD images. NIR observations reveal that dust extinctiondoes almost not influence the shape of bulges. There is no substantialdifference between the shape of bulges in the optical and in the NIR.Our analysis reveals that 45% of all bulges are box- and peanut-shaped(b/p). The frequency of b/p bulges for all morphological types from S0to Sd is > 40%. In particular, this is for the first time that such alarge frequency of b/p bulges is reported for galaxies as late as Sd.The fraction of the observed b/p bulges is large enough to explain theb/p bulges by bars. Partly based on observations collected at ESO/LaSilla (Chile), DSAZ/Calar Alto (Spain), and Lowell Observatory/Flagstaff(AZ/U.S.A.). Tables 6 and 7 are only available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| 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.
| Molecular Gas, Morphology, and Seyfert Galaxy Activity
We probe the cause of the elevated star formation in host galaxies ofSeyfert 2 nuclei compared with Seyfert 1 hosts and with field galaxies.12CO (1--0) observations of a large sample of Seyfert galaxies indicateno significant difference in the total amount of molecular gas as afunction of the Seyfert nuclear type, nor are Seyfert galaxiessignificantly different in this regard from a sample of field galaxiesonce selection effects are accounted for. Therefore, the total amount ofmolecular gas is not responsible for the enhanced star-forming activityin Seyfert 2 hosts. To probe how this gas is being converted moreefficiently into stars in Seyfert 2 hosts than in the other galaxies, weinvestigate the occurrence of bars, interactions, and distortedmorphologies among Seyfert galaxies. We find a significantly higher rateof asymmetric morphologies for Seyfert 2 galaxies with respect toSeyfert 1 galaxies and field galaxies. Relative to field galaxies, theeffect is at a greater than 99.9% confidence level. The presence ofasymmetric morphologies in individual Seyfert galaxies is correlatedwith their tendency to exhibit enhanced star-forming activity. Theseresults suggest that asymmetric morphologies are an important cause forthe link between Seyfert type and star-forming activity: bars anddistortions in Seyfert 2 hosts are likely both to enhance star-formingactivity and to funnel gas into the nuclear region, thus obscuring andpossibly contributing to the feeding of the active nucleus.
| 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.
| Total and effective colors of 501 galaxies in the Cousins VRI photometric system
Total color indices (V-R)T, (V-I)T and effectivecolor indices (V-R)e, (V-I)e in the Cousins VRIphotometric system are presented for 501 mostly normal galaxies. Thecolors are computed using a procedure outlined in the Third ReferenceCatalogue of Bright Galaxies (RC3) whereby standard color curvesapproximated by Laplace-Gauss integrals are fitted to observedphotoelectric multiaperture photometry. 11 sources of such photometrywere used for our analysis, each source being assigned an appropriateweight according to a rigorous analysis of residuals of the data fromthe best-fitting standard color curves. Together with the integrated B-Vand U-B colors provided in RC3, our analysis widens the range ofwavelength of homogeneously defined colors of normal galaxies of allHubble types. We present color-color and color-type relations that canbe modeled to understand the star formation history of galaxies.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| The dependence of the cool matter content on galaxy morphology in galaxies of types E/S0, S0, and SA
Using the material assembled in earlier papers, we examine the manner inwhich the interstellar matter content varies along the Hubble sequencefrom S0 galaxies to Sa galaxies selected from the RSA2 compilation. Forthis we make use of a new and more detailed classification which isdescribed here as applied to these early disk/spiral galaxies. Theprominence of the disk in S0's and the visibility of features (H IIregions) in the Sa's serve as the basis for the subtypes. Three S0categories: subtle, intermediate, and pronounced, and four Sadescriptors: very early, early, intermediate, and late are assigned tothe galaxies. It is found that the total amount of hydrogen (H I + H2)is a function of subtype, being low in the S0's and rising smoothly fromthe early Sa's to the later Sa's. The average surface density ofhydrogen exceeds 3 solar masses/pc-squared only in the latest subtypesof the Sa's. We conclude that the prominence of the disk of a galaxyclosely follows the amount of cool gas which the disk contains.
| General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| Interstellar matter in early-type galaxies. II - The relationship between gaseous components and galaxy types
Interstellar components of early-type galaxies are established bygalactic type and luminosity in order to search for relationshipsbetween the different interstellar components and to test thepredictions of theoretical models. Some of the data include observationsof neutral hydrogen, carbon monoxide, and radio continuum emission. Analternative distance model which yields LX varies as LB2.45,a relation which is in conflict with simple cooling flow models, isdiscussed. The dispersion of the X-ray luminosity about this regressionline is unlikely to result from stripping. The striking lack of clearcorrelations between hot and cold interstellar components, takentogether with their morphologies, suggests that the cold gas is a diskphenomenon while the hot gas is a bulge phenomenon, with littleinteraction between the two. The progression of galaxy type from E to Sais not only a sequence of decreasing stellar bulge-to-disk ratio, butalso of hot-to-cold-gas ratio.
| 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.
| Southern Sky Redshift Survey - The catalog
The catalog of radial velocities for galaxies which comprise thediameter-limited sample of the Southern Sky Redshift Survey ispresented. It consolidates the data of observations carried out at theLas Campanas Observatory, Observatorio Nacional, and South AfricanAstronomical Observatory. The criteria used for the sample selection aredescribed, as well as the observational procedures and the techniqueutilized to obtain the final radial velocities. The intercomparisonbetween radial velocity measurements from different telescopes indicatesthat the final data base is fairly homogeneous with a typical error ofabout 40 km/s. The sample is at present 90 percent complete, and themissing galaxies are predominantly objects with very low surfacebrightness for which it is very difficult to obtain optical redshifts.
| Interstellar matter in early-type galaxies. I - The catalog
A catalog is given of the currently available measurements ofinterstellar matter in the 467 early-type galaxies listed in the secondedition of the Revised Shapley-Ames Catalog of Bright Galaxies. Themorphological type range is E, SO, and Sa. The ISM tracers are emissionin the following bands: IRAS 100 micron, X-ray, radio, neutral hydrogen,and carbon monoxide. Nearly two-thirds of the Es and SOs have beendetected in one or more of these tracers. Additional observed quantitiesthat are tabulated include: magnitude, colors, radial velocity, centralvelocity dispersion, maximum of the rotation curve, angular size, 60micron flux, and supernovae. Qualitative statements as to the presenceof dust or emission lines, when available in the literature, are given.Quantities derivative from the observed values are also listed andinclude masses of H I, CO, X-ray gas, and dust as well as an estimate ofthe total mass and mass-to-luminosity ratio of the individual galaxies.
| H I content and FIR emission of S0 galaxies
A sample of 252 S0 galaxies is used to study the relationship between HI content and far-IR emission. Logarithms of the H I content versus thefar-IR emission are employed statistically to develop a best-fit linearregression line which is compared to a slope of approximately unity. Theslopes are different for S0 and SB0 galaxies versus S0/a and SB0/agalaxies. The distribution of the 60-100 micron flux ratio is notsignificantly affected by the presence or absence of bars nor by thedifferences between the S0 and S0/a systems. The flux ratio is higherthan the critical value of Helou in 34 percent of the cases, and thevalue holds when nuclear emission is taken into account. In cases wherethe critical value is exceeded, most far-IR emissions are expected to bedue to star formation. S0 galaxies are generally found to have a normalISM, except where the systems have accreted their H I gas. Systems withdisproportionate FIR emission can be considered galaxies that areexperiencing enhanced star formation or that have had their H I gasswept away.
| An extended galaxy redshift survey. I - The catalogue
Redshifts and blue magnitudes are presented for a sample of 264 'field'galaxies virtually complete to a limiting magnitude of 16.80 mag. Thegalaxies were selected by sampling one galaxy in every three in order ofapparent magnitude on each of nine high-latitude UK Schmidt (UKST)fields. The spectral data came from observations with the 1.9-mtelescope at the South African Astronomical Observatory (SAAO), and theresulting radial velocities have a precision of 130 + or - km/s. Thissurvey augments substantially the Durham/AAT redshift survey. Theobservational techniques and reduction procedures are discussed.
| A catalog of southern groups of galaxies
A catalog of groups of galaxies identified in the southern Galactic capis presented. This catalog was constructed utilizing the group-findingalgorithm developed by Huchra and Geller (1982) to analyze galaxysamples with well-defined selection criteria and complete velocityinformation.
| Revised supernova rates in Shapley-Ames galaxies
Observations of 855 Shapley Ames galaxies made from November 1, 1980 toOctober 31, 1988, together with improved supernova luminosities, havebeen used to derive the frequency of supernovae of different types, andthe results are presented in tables. From a uniform database of 24supernovae discovered, the following SN rates are found, expressed in SNper century per 10 to the 10th L(B)(solar): SN Ia, 0.3; SN Ib, 0.3; andSN II, 1.0. The present data confirm the relatively high frequency of SNII in late-type galaxies that has been found by many previousinvestigators.
| The ON-CfA redshift survey of the southern hemisphere
A redshift survey of a diameter-limited sample of southern galaxies hasbeen performed by the Observatorio Nacional in collaboration with theHarvard-Smithsonian Center for Astrophysics. Redshift data are presentedfor 442 galaxies. A relatively small mean difference of -5.2 km/s wasfound between the present redshifts and previous radio data.
| UBVRI aperture photometry of early-type galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1988A&AS...72..215P&db_key=AST
| The supernova rate in Shapley-Ames galaxies
A visual search for SNs in 748 Shapley-Ames galaxies during the 5-yearperiod from November 1, 1980 to October 31, 1985 has yielded SN rates of0.3h-squared, 0.4h-squared, and 1.1h-squared for objects of types Ia,Ib, and II, respectively. These data are judged to imply that Tammann's(1974, 1982) SN rates are probably too high by a factor of about 3. Fora Galactic luminosity of 2 x 10 to the 10th solar L(B), the predicted SNrates in the Milky Way system are 0.6h-squared, 0.8h-squared, and2.2h-squared/century, respectively, for the three aforementioned types.
| The statistical distribution of the neutral-hydrogen content of S0 galaxies
The distribution of relative global H I content M(H I)/L(B) has beenderived for galaxies of types S0 and S0/a using a data set derived fromrecent H I observations in the literature. The relative H I content ofthese galaxies is found to show transitional properties betweenelliptical and spiral galaxies. The distribution of M(H I)/L(B) forS0/a's resembles that for spirals, and these galaxies may represent'fossil' spirals, i.e., galaxies whose gas has been severely depleted bystar formation. The distribution for S0's, however, resembles that forellipticals. The form of this distribution strongly suggests an externalorigin for most of the H I in S0 galaxies.
| A catalog of 2810 nearby galaxies - The effect of the Virgocentric flow model on their observed velocities
A catalog of 2810 nearby galaxies is constructed on the basis of threesubcatalogs: galaxies with B(T) less than or equal to 13.4 mag, galaxieswith v0 less than or equal to 500 km/s, and galaxies having B(T) lessthan or equal to 14.95 mag and lying within a 10-deg cone around M87.The data are compiled in tables and graphs and characterized in detail.The distances to objects with known red shifts are determined in unitsof the Virgo-cluster distance, independent of H0, using two versions ofthe nonlinear Virgocentric-flow models of Silk (1974 and 1977) and shownto correspond to local Virgo-inflow rates of 220 and 440 km/s,respectively. The luminous-galaxy distribution is described as acell-like structure with several superclusters, chains ofinterconnecting galaxies, and large voids.
| VRI aperture photometry of southern E and SO galaxies
VRI aperture photometry of 115 E and SO southern galaxies is presented.Out of this number, 86 objects had never been observed through the Ifilter. The results are in good agreement with other observations.
| Southern Galaxy Catalogue.
Not Available
| A comparison of distance scales for early-type galaxies
The distance scales of elliptical and lenticular galaxies areintercompared, based on the velocity dispersion indicator derived from arevised Faber-Jackson relation. The scales are found to be in nearperfect agreement with scales derived from the luminosity index and fromthe 21 cm line width indicator. The scales are also in excellentagreement with the distance scale derived by Michard (1979). Additionsare offered for the general catalog of 424 early-type galaxies, and aseries of reduction equations is presented which reduces the externalerrors in the distance moduli.
| UBVRI photoelectric photometry of 191 southern galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984A&AS...58..249L&db_key=AST
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