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Supermassive black hole mass measurements for NGC 1300 and 2748 based on Hubble Space Telescope emission-line gas kinematics
We present Space Telescope Imaging Spectrograph emission-line spectra ofthe central regions of the spiral galaxies NGC 1300 and 2748. From thederived kinematics of the nuclear gas we have found evidence for centralsupermassive black holes in both galaxies. The estimated masses of theblack holes in NGC 1300 and 2748 are (6.6+6.3-3.2)× 107 and (4.4+3.5-3.6) ×107 Msolar, respectively (both at the 95 per centconfidence level). These two black hole mass estimates contribute to thepoorly sampled low-mass end of the nuclear black hole mass spectrum.
| 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 catalogue and analysis of X-ray luminosities of early-type galaxies
We present a catalogue of X-ray luminosities for 401 early-typegalaxies, of which 136 are based on newly analysed ROSAT PSPC pointedobservations. The remaining luminosities are taken from the literatureand converted to a common energy band, spectral model and distancescale. Using this sample we fit the LX:LB relationfor early-type galaxies and find a best-fit slope for the catalogue of~2.2. We demonstrate the influence of group-dominant galaxies on the fitand present evidence that the relation is not well modelled by a singlepower-law fit. We also derive estimates of the contribution to galaxyX-ray luminosities from discrete-sources and conclude that they provideLdscr/LB~=29.5ergs-1LBsolar-1. Wecompare this result with luminosities from our catalogue. Lastly, weexamine the influence of environment on galaxy X-ray luminosity and onthe form of the LX:LB relation. We conclude thatalthough environment undoubtedly affects the X-ray properties ofindividual galaxies, particularly those in the centres of groups andclusters, it does not change the nature of whole populations.
| Stellar populations in dwarf elliptical galaxies.
Not Available
| 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
| The fundamental plane of early-type galaxies: stellar populations and mass-to-light ratio.
We analyse the residuals to the fundamental plane (FP) of ellipticalgalaxies as a function of stellar-population indicators; these are basedon the line-strength parameter Mg_2_ and on UBVRI broad-band colors, andare partly derived from new observations. The effect of the stellarpopulations accounts for approximately half the observed variation ofthe mass-to-light ratio responsible for the FP tilt. The residual tiltcan be explained by the contribution of two additional effects: thedependence of the rotational support, and possibly that of the spatialstructure, on the luminosity. We conclude to a constancy of thedynamical-to-stellar mass ratio. This probably extends to globularclusters as well, but the dominant factor would be here the luminositydependence of the structure rather than that of the stellar population.This result also implies a constancy of the fraction of dark matter overall the scalelength covered by stellar systems. Our compilation ofinternal stellar kinematics of galaxies is appended.
| A Catalog of Stellar Velocity Dispersions. II. 1994 Update
A catalog of central velocity dispersion measurements is presented,current through 1993 September. The catalog includes 2474 measurementsof 1563 galaxies. A standard set of 86 galaxies is defined, consistingof galaxies with at least three reliable, concordant measurements. It issuggested that future studies observe some of these standard galaxies sothat different studies can be normalized to a consistent system. Allmeasurements are reduced to a normalized system using these standards.
| A multiparametric analysis of the Einstein sample of early-type galaxies. 1: Luminosity and ISM parameters
We have conducted bivariate and multivariate statistical analysis ofdata measuring the luminosity and interstellar medium of the Einsteinsample of early-type galaxies (presented by Fabbiano, Kim, &Trinchieri 1992). We find a strong nonlinear correlation betweenLB and LX, with a power-law slope of 1.8 +/- 0.1,steepening to 2.0 +/- if we do not consider the Local Group dwarfgalaxies M32 and NGC 205. Considering only galaxies with logLX less than or equal to 40.5, we instead find a slope of 1.0+/- 0.2 (with or without the Local Group dwarfs). Although E and S0galaxies have consistent slopes for their LB-LXrelationships, the mean values of the distribution functions of bothLX and LX/LB for the S0 galaxies arelower than those for the E galaxies at the 2.8 sigma and 3.5 sigmalevels, respectively. We find clear evidence for a correlation betweenLX and the X-ray color C21, defined by Kim,Fabbiano, & Trinchieri (1992b), which indicates that X-rayluminosity is correlated with the spectral shape below 1 keV in thesense that low-LX systems have relatively large contributionsfrom a soft component compared with high-LX systems. We findevidence from our analysis of the 12 micron IRAS data for our samplethat our S0 sample has excess 12 micron emission compared with the Esample, scaled by their optical luminosities. This may be due toemission from dust heated in star-forming regions in S0 disks. Thisinterpretation is reinforced by the existence of a strongL12-L100 correlation for our S0 sample that is notfound for the E galaxies, and by an analysis of optical-IR colors. Wefind steep slopes for power-law relationships between radio luminosityand optical, X-ray, and far-IR (FIR) properties. This last point arguesthat the presence of an FIR-emitting interstellar medium (ISM) inearly-type galaxies is coupled to their ability to generate nonthermalradio continuum, as previously argued by, e.g., Walsh et al. (1989). Wealso find that, for a given L100, galaxies with largerLX/LB tend to be stronger nonthermal radiosources, as originally suggested by Kim & Fabbiano (1990). We notethat, while LB is most strongly correlated withL6, the total radio luminosity, both LX andLX/LB are more strongly correlated with L6CO, the core radio luminosity. These points support the argument(proposed by Fabbiano, Gioia, & Trinchieri 1989) that radio cores inearly-type galaxies are fueled by the hot ISM.
| A Multiparametric Analysis of the Einstein Sample of Early-Type Galaxies. III. Comparisons with the kappa -Parameters
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...448...70E&db_key=AST
| A multiparametric analysis of the Einstein sample of early-type galaxies. 2: Galaxy formation history and properties of the interstellar medium
We have conducted bivariate and multivariate statistical analysis ofdata measuring the integrated luminosity, shape, and potential depth ofthe Einstein sample of early-type galaxies (presented by Fabbiano et al.1992). We find significant correlations between the X-ray properties andthe axial ratios (a/b) of our sample, such that the roundest systemstend to have the highest Lx and Lx/LB.The most radio-loud objects are also the roundest. We confirm theassertion of Bender et al. (1989) that galaxies with high Lxare boxy (have negative a4). Both a/b and a4 arecorrelated with LB, but not with IRAS 12 um and 100 umluminosities. There are strong correlations between Lx,Mg2, and sigmanu in the sense that those systemswith the deepest potential wells have the highest Lx andMg2. Thus the depth of the potential well appears to governboth the ability to retain an ISM at the present epoch and to retain theenriched ejecta of early star formation bursts. BothLx/LB and L6 (the 6 cm radioluminosity) show threshold effects with sigmanu exhibitingsharp increases at log sigmanu approximately = 2.2. Finally,there is clearly an interrelationship between the various stellar andstructural parameters: The scatter in the bivariate relationshipsbetween the shape parameters (a/b and a4) and the depthparameter sigmanu is a function of abundance in the sensethat, for a given a4 or a/b, the systems with the highestsigmanu also have the highest Mg2. Furthermore,for a constant sigma(sun nu), disky galaxies tend to have higherMg2 than boxy ones. Alternatively, for a given abundance,boxy ellipticals tend to be more massive than disky ellipticals. Onepossibility is that early-type galaxies of a given mass, originatingfrom mergers (boxy ellipticals), have lower abundances than 'primordial'(disky) early-type galaxies. Another is that disky inner isophotes aredue not to primordial dissipation collapse, but to either theself-gravitating inner disks of captured spirals or the dissipationalcollapse of new disk structures from the premerger ISM. The highmeasured nuclear Mg2 values would thus be due to enrichmentfrom secondary bursts of star formation triggered by the merging event.
| Dynamically hot galaxies. II - Global stellar populations
The global relationship between the stellar populations and thestructural properties of dynamically hot galaxies (DHGs) is investigatedusing the same sample as was analyzed by Bender et al. (1992), whichincludes giant ellipticals, low-luminosity ellipticals, compactellipticals, diffuse dwarf ellipticals, dwarf spheroidals, and bulges.It was found that all DHGs follow a single relationship between globalstellar population (represented by Mg2 index or B-V color) and centralvelocity dispersion sigma(0), and that the Mg2-sigma(0) relation issignificantly tighter than the relation between the Mg2 index andabsolute luminosity. The relation between central Mg2 index and bulk B-Vcolor was also found to be tight.
| 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.
| A list of some corrections to Zwicky's Catalogue of Galaxies and Clusters of Galaxies
Not Available
| An X-ray catalog and atlas of galaxies
An X-ray catalog and atlas of galaxies observed with the EinsteinObservatory imaging instruments (IPC and HRI) are presented. The catalogcomprises 493 galaxies, including targets of pointed observations, andRSA or RC2 galaxies serendipitously included in Einstein fields. A totalof 450 of these galaxies were imaged well within the instrumentalfields, resulting in 238 detections and 2123 sigma upper limits. Theother galaxies were either at the edge of the visible field of view orconfused with other X-ray sources. For these a rough measure of theirX-ray emission is also given. The atlas shows X-ray contour maps ofdetected galaxies superposed on optical photographs and givesazimuthally averaged surface brightness profiles of galaxies detectedwith a high signal-to-noise ratio.
| Dynamically hot galaxies. I - Structural properties
Results are reported from an analysis of the structural properties ofdynamically hot galaxies which combines central velocity dispersion,effective surface brightness, and effective radius into a new 3-space(k), in which the axes are parameters that are physically meaningful.Hot galaxies are found to divide into groups in k-space that closelyparallel conventional morphological classifications, namely, luminousellipticals, compacts, bulges, bright dwarfs, and dwarf spheroidals. Amajor sequence is defined by luminous ellipticals, bulges, and mostcompacts, which together constitute a smooth continuum in k-space.Several properties vary smoothly with mass along this continuum,including bulge-to-disk ratio, radio properties, rotation, degree ofvelocity anisotropy, and 'unrelaxed'. A second major sequence iscomprised of dwarf ellipticals and dwarf spheroidals. It is suggestedthat mass loss is a major factor in hot dwarf galaxies, but the dwarfsequence cannot be simply a mass-loss sequence, as it has the wrongdirection in k-space.
| The shape of central regions in elliptical galaxies
Isophote analysis of high-resolution CCD images of a large sample of 75early-type, mostly elliptical, galaxies indicates that 25 of theseobjects harbor central bodies that appear separate from the rest of thegalaxy, and whose sizes are in the 2-10-arcsec range. Fifteen of these25 central substructures exhibit clearly 'pointed' isophotes, and allobjects known to have decoupled core kinematics exhibit a photometricsubstructure coinciding in radius with the kinematic substructure.Several arguments suggest that these central substructures are disks.
| Associations between quasi-stellar objects and galaxies
A table is presented here listing all close pairs of QSOs and galaxiesthat were found in a computer-aided search of catalogs of QSOs andbright galaxies and an extensive search of the literature. There is alarge excess of pairs with separations of 2 arcmin lor less, or about 60kpc, over the numbers expected if the configurations were accidental.The angular separation for 392 pairs adds to the evidence for physicalassociation, and it is shown that selection effects are not important. Ageneral rule is stated that QSOs tend to lie in the vicinity of normalgalaxies much more often than is expected by chance whether or not thegalaxies and the QSOs have the same redshifts. It is emphasized thatthis rule cannot be explained in terms of gravitational microlensing,and it is concluded that some part of the redshift of all classes ofactive nuclei is not associated with the expansion of the universe.
| Internal kinematics of low-luminosity ellipsoidal galaxies
Spectroscopic observations are presented of ten low-mass ellipsoidalgalaxies having luminosities in the range where the luminosity functionsof luminous ellipticals and low surface-brightness dwarf ellipticalsoverlap. The sample covers a large range in effective surfacebrightness, from values typical of genuine dwarfs to those of compact, M32-like, ellipticals. In contrast to what may be expected from theextrapolation of the result of Davies et al. (1983), about half of theobjects are not rotationally flattened. However, only objects fainterthan M(T) = -18.0 mag and having low surface brightness are considerablyanisotropic, indicating that: (1) the result of Davies et al. (1983)still describes the overall trend between kinematics and luminosity forelliptical galaxies brighter than M(T) = -18 mag in the correct way, and(2) low surface brightness dwarf ellipsoidals may be in general notrotationally flattened.
| The low-mass extension of the fundamental plane of elliptical galaxies
A sample of 17 low-mass elliptical and elliptical-like galaxies wasbuilt with accurate photometric and spectroscopic data. This sample,covering a wide range in surface brightness, is in or near the low-massextension of the 'fundamental plane' defined by bright ellipticals, butshows a scatter which cannot be accounted for by measurement errors andwhich is thus probably due to a large variety of internal structures.Extending the analysis to globular clusters and dwarf spheroidals, it isfound that they are also near or within the fundamental plane, exceptfor two dwarfs suspected of having a high M/L. The range thus covered is20 in absolute magnitude. These results suggest that the fundamentalplane is a robust representation of the virial theorem, valid forellipticals and for other types of pressure-supported stellar systems aswell. It also indicates that the standard parameter relations are littlesensitive to specific formation processes, local environment, andstructural details, that may have an effect at a subtler level.
| Hierarchical pairs and the evolution of elliptical galaxies
Consideration is given to the photometric and kinematic characteristicsof galaxies in eight close pairs of ellipticals consisting of a brightgalaxy and a compact faint companion. Redshifts and central velocitydispersions are determined from high-dispersion spectra. Evidence ispresented for interaction in the pairs. The mean surface brightness andcentral velocity dispersions of the galaxies are tightly correlated withluminosity. Two sequences of ellipticals are defined, based on the workof Michard (1979). The galaxies in this study are sequence I galaxies.It is suggested that sequence II galaxies evolve toward sequence Igalaxies through dissipation of internal energy and loss of angularmomentum.
| Radio identifications of IRAS point sources with B greater than 30 deg
The present radio identifications of IRAS point sources on the basis ofGreen Bank 1400 MHz survey maps notes that 365 'hot' IR sources are notdetectable radio sources, and that nearly all 'cool' high latitude IRASsources are extragalactic. The fainter IR-source identificationsencompass optically bright quasars, BL Lac objects, Seyfert galaxies,and elliptical galaxies. No IRAS sources could be identified withdistant elliptical radio galaxies, so that although the radio and IRfluxes of most IRAS extragalactic sources are tightly correlated,complete samples of strong radio and IR sources are almost completelydisjoint; no more than 1 percent of the IR sources are radio sources andless than 1 percent of the radio sources are IR ones.
| Radio continuum emission of nearby elliptical galaxies Statistical properties
A sample of 123 elliptical galaxies is compiled from optically selectedsamples observed at 1.4 GHz with the Westerbork Synthesis RadioTelescope. The analysis of the sample properties confirms thecorrelation of the radio continuum emission with optical luminosity, gascontent and roundness, but no indications for the influence of theenvironment are found. These results are discussed in relation to thehypothesis that accretion of gas onto the galaxy center is responsiblefor the radio emission.
| UBV-photometry of some double galaxies.
Not Available
| A Survey of Elliptical Galaxies at 6 CM
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....24..247E&db_key=AST
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