Upload your image
DSS Images Other Images
Submit a new article
|Redshift-Distance Survey of Early-Type Galaxies: Spectroscopic Data|
We present central velocity dispersions and Mg2 line indicesfor an all-sky sample of ~1178 elliptical and S0 galaxies, of which 984had no previous measures. This sample contains the largest set ofhomogeneous spectroscopic data for a uniform sample of ellipticalgalaxies in the nearby universe. These galaxies were observed as part ofthe ENEAR project, designed to study the peculiar motions and internalproperties of the local early-type galaxies. Using 523 repeatedobservations of 317 galaxies obtained during different runs, the dataare brought to a common zero point. These multiple observations, takenduring the many runs and different instrumental setups employed for thisproject, are used to derive statistical corrections to the data and arefound to be relatively small, typically <~5% of the velocitydispersion and 0.01 mag in the Mg2 line strength. Typicalerrors are about 8% in velocity dispersion and 0.01 mag inMg2, in good agreement with values published elsewhere.
|The Active Merging System ESO 202-G23 (Carafe Nebula)|
We present the results of observations both in imaging and spectroscopyof the nearby active galaxy ESO 202-G23 (Carafe Nebula). The main resultof this investigation is that the peculiar morphology of the galaxy,formerly attributed to the presence of an asymmetric bar, is produced bythe merging of two galaxies both hosting an active nucleus. Our deep Rimage reveals unexpectedly the presence of a knot (G2), not visible inthe B image, at 3.5 kpc on the northern of the nucleus (G1), classifiedin the literature as a Seyfert 2. A long-slit spectrum provides evidencethat G1 is a Seyfert 1.5 nucleus and that G2 is also a nucleus, showingfeatures typical of a LINER heavily reddened by dust. The presence oftails and plumes in the outermost parts of the galaxy and the double Ushape of the rotation curve of the gas around G1 and G2 strongly supportthe hypothesis of a merger that occurred 106-109years ago, as suggested by the comparison of the current (14Msolar yr-1) and the recent (24 Msolaryr-1) star formation rates. The system ESO 202-G23 is aninfrared bright source(LFIR/Lsolar=2.18×1010) and theIRAS flux ratios suggest a predominantly thermal origin of the infraredemission. The analysis of the IRAS data allows us to obtain someimportant properties concerning both the gas and the dust:Td(warm)~36 K; Md(warm)=4.1×106Msolar Td(cold)~21 K;Md(cold)=(6.9-8.3)×107 MsolarMHI=8.6×109 MsolarMHII=(2.3-4.3)×109 MsolarMgas=(1.1-1.3)×1010 Msolar. Thederived mass-to-light ratio MHI/LB=2.23 and thevalue of the parameter K=vmax/rmax, K(G1)=201,K(G2)=179, indicate that the precursor is not later than Sbc. Based onobservations collected at ESO, La Silla, Chile.
|Southern Isolated Galaxy Triplets|
Seventy-six isolated triple systems of galaxies with declinatiosnδ<-3° were selected using ESO/SERC and POSS-I sky surveydata. The equatorial coordinates, configuration types, angular sizes,component angular separations, component morphological types, totalmagnitudes, and other parameters are reported for each triplet.Radial-velocity estimates are available for all components in 33 of the76 triplets. The median values of the main dynamicalparametersradial-velocity dispersion, mean harmonic radius,absolute magnitudes of member galaxies, and mass-to-luminosityratiosare similar to those obtained earlier for 83 isolatedtriple systems with δ>-3°.
|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.
|A Test for Large-Scale Systematic Errors in Maps of Galactic Reddening|
Accurate maps of Galactic reddening are important for a number ofapplications, such as mapping the peculiar velocity field in the nearbyuniverse. Of particular concern are systematic errors which vary slowlyas a function of position on the sky, as these would induce spuriousbulk flow. We have compared the reddenings of Burstein & Heiles (BH)and those of Schlegel, Finkbeiner, & Davis (SFD) to independentestimates of the reddening, for Galactic latitudes |b|>10^deg. Ourprimary source of Galactic reddening estimates comes from comparing thedifference between the observed B-V colors of early-type galaxies, andthe predicted B-V color determined from the B-V-Mg_2 relation. We havefitted a dipole to the residuals in order to look for large-scalesystematic deviations. There is marginal evidence for a dipolar residualin the comparison between the SFD maps and the observed early-typegalaxy reddenings. If this is due to an error in the SFD maps, then itcan be corrected with a small (13%) multiplicative dipole term. Weargue, however, that this difference is more likely to be due to a small(0.01 mag) systematic error in the measured B-V colors of the early-typegalaxies. This interpretation is supported by a smaller, independentdata set (globular cluster and RR Lyrae stars), which yields a resultinconsistent with the early-type galaxy residual dipole. BH reddeningsare found to have no significant systematic residuals, apart from theknown problem in the region 230^deg
|Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies|
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
|A catalogue of Mg_2 indices of galaxies and globular clusters|
We present a catalogue of published absorption-line Mg_2 indices ofgalaxies and globular clusters. The catalogue is maintained up-to-datein the HYPERCAT database. The measurements are listed together with thereferences to the articles where the data were published. A codeddescription of the observations is provided. The catalogue gathers 3541measurements for 1491 objects (galaxies or globular clusters) from 55datasets. Compiled raw data for 1060 galaxies are zero-point correctedand transformed to a homogeneous system. Tables 1, 3, and 4 areavailable in electronic form only at the CDS, Strasbourg, via anonymousftp 184.108.40.206. Table 2 is available both in text and electronic form.
|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.
|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.
|The Catalog of Southern Ringed Galaxies|
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
|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.
|Optical galaxies within 8000 km s-1 - IV. The peculiar velocity field|
The density field of optically selected galaxies within 8000 kms-1 is used to predict the peculiar velocities ofDn-σ and IRTF galaxies employing linear gravitationalinstability theory. To obtain acceptable fits to the observed peculiarvelocities in the CMB frame, it is necessary to fit two parameters:B0 = Ω0.6b0-1(whereb0 is a biasing parameter for optical galaxies), which scalesthe predictions of the optical density field within 8000 kms-1; and a residual bulk motion due to sources outside thevolume. The fits yield β0 = 0.50+/-0.06(1σ randomerrors) for both the IRTF and the Dn-σ samples, and aresidual bulk motion of 405+/-45 km s-1 towards l =292deg, b= 7deg for the IRTF field galaxies. Thereis no evidence for a mass concentration in the zone of avoidance within8000 km s-1 whose effect on the Local Group is more than 100km s-1, so the residual bulk motion must be due primarily tosources beyond 8000 km s-1. The result for β0corresponds to Ω = 0.32 +/- 0.06 if mass traceslight(b0 = 1), or to b0 = 2.0+/-0.24 if Ω =1. If biasing is independent of scale, then taken together these resultsare inconsistent with the predictions of the standard cold dark mattercosmology for any choice of the biasing parameter, but are compatiblewith cosmological models that fit the galaxy number counts on largescales.
|Optical galaxies within 8000 km s-1 - III. Inhomogeneous Malmquist bias corrections and the Great Attractor.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.266..468H&db_key=AST
|Low-luminosity radio sources in early-type galaxies|
A sensitive radio continuum survey of 114 nearby E and S0 galaxies hasbeen made to search for weak sources. The radio detection rate is 42percent, with a flux limit of 0.8 mJy at 5 GHz. By deriving the radioluminosity function for a complete sample, it is shown that most brightearly-type galaxies have low-luminosity nonthermal radio sources.Galaxies of similar optical luminosity vary widely in radio luminosity,but a characteristic radio power rises roughly as the optical luminositysquared. S0 galaxies have weaker radio sources on average thanelliptical galaxies, but this can be explained by the low luminosity ofmost S0 bulges relative to ellipticals. No correlation is found betweenradio power and axial ratio for galaxies with radio luminosities below10 to the 23rd W/Hz.
|On the relationship between radio emission and optical properties in early-type galaxies|
To study the origin of radio activity in early-type galaxies, thepossible dependence of their radio emission on basic optical parameters,such as the absolute magnitude, the central velocity dispersion sigma,and the mean surface brightness mu is explored. A sample of 743 E and SOgalaxies is used which is based on three independent radio surveys ofoptically selected galaxies with virtually complete information onmagnitudes, morphological types, redshift distances, diameters, andradio fluxes. For both E and SO galaxies, only the absolute magnitudeappears to be directly related to the radio activity, while sigma and mudo not. Also, a significant dependence of the apparent flattening onradio power is confirmed for E galaxies. Some relevant implications ofthese results are discussed.
|Surface photometry of southern elliptical galaxies|
The results of a surface photometry survey for 131 elliptical galaxiesin the southern hemisphere are presented. In this paper isophotal mapsand major-axis profiles are shown, deriving for each galaxy in thesample structural parameters using the de Vaucouleurs law as usefulparametric descriptor of the light distribution of elliptical galaxies.
|Spectroscopy and photometry of elliptical galaxies. V - Galaxy streaming toward the new supergalactic center|
The dynamics of 400 elliptical galaxies in an all-sky survey areanalyzed. The motions of the elliptical galaxies, over and above Hubbleexpansion in the CMB frame, are best fitted by a flow toward a greatattractor (GA) centered on l = 307, b = 9, at a distance of R(m) = 4350+ or - 350 km/s in the Hubble flow. The excess mass must be about 5.4 x10 to the 16th solar masses, comparable to the largest superclusters, inorder to generate the streaming motion at the sun of 570 + or - 60 km/s.A picture of the hemisphere of sky centered on the direction toward theGA shows a remarkable concentration of galaxies in Centaurus that issome 20 times more populous than the Virgo cluster. The cosmologicalimplications of the findings are discussed.
|Spectroscopy and photometry of elliptical galaxies. III - UBV aperture photometry, CCD photometry, and magnitude-related parameters|
Photoelectric aperture photometry of nearly 2000 individual observationsof 449 elliptical galaxies combined with published measurements usingthe self-consistent UVB color catalog developed by Burstein et al.(1987) are presented. The data are placed on a standard magnitude andcolor system, and 'total' magnitudes and effective diameters are derivedby comparison with the standard elliptical magnitude growth curve. Agraphical representation of the standard growth curve and the residualsfrom it for each galaxy are given, and a new diameter measurement Dn ispresented which can be measured reliably for elliptical galaxies andserves as an accurate distance indicator when combined with centralvelocity dispersion. Individual magnitudes, surface brightnesses,effective diameters, and values of Dn are summarized for each galaxy incatalog form.
|Spectroscopy and photometry of elliptical galaxies. II - The spectroscopic parameters|
Radial velocities, velocity dispersions, and Mg line-strength indicesare measured for 469 elliptical galaxies using four telescope/detectorconfigurations. The data have been put on a common scale; the scatter ofrepeat measurements indicates an uncertainty of + or - 10 percent and +or - 0.01 mag for single determinations of sigma and Mg2, respectively.A correction for the change in linear aperture size as a function ofdistance has been derived, and mean corrected values of sigma and Mg2are adopted. The galaxies have been assigned to groups by combining thepresent velocities with those in the redshift catalog of Huchra et al.(1983) and using the algorithm of Huchra and Geller (1982).
|BV photometry of southern elliptical galaxies|
Photometric data for 78 elliptical galaxies observed in V and B colorswith the Cerro Tololo Inter-American Observatory 0.9-m telescope duringApril and November 1983 are examined. Lamberts' data from the ESO surveyof the ESO (B) Atlas are presented. The data are analyzed in order tostudy the motion of the Local Group and the spatial distribution ofgalaxies in the local region of the universe. The photometric data arecompared to the data in the photometry catalog of Longo and deVaucouleurs (1983, 1985) and good correlation between the observationsis detected.
|Ionized gas in elliptical and S0 galaxies. I - A survey for H-alpha and forbidden N II emission|
A spectroscopic survey of a large sample of southern E and S0 galaxiesin order to detect ionized gas in the nuclei is reported. The strongestline in the 6000-7000 A range was nearly always forbidden N II 6584 A,followed by H-alpha and forbidden S II 6716, 6731 A. Identical detectionrates of about 50 percent were obtained for the forbidden N II line inboth E and S0 galaxies. The mass of ionized gas in early-type galaxieswas very small, with values typically in the range 1000-10,000 solarmasses. The relative emission-line strengths in virtually every casewere indistinguishable from those of LINER nuclei. The observed valuesof the forbidden N II 6584 A/H-alpha ratios fell mostly between one andthree and seem correlated with galaxy absolute magnitude. The existenceof such a correlation may be indicative of metallicity differences.
|Southern Galaxy Catalogue.|
|Radio and optical observations of a complete sample of E and SO galaxies. III. A radio continuum survey at 2.7 and 5.0 GHz.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...53S&db_key=AST
|Radio and optical observations of a complete sample of E and SO galaxies. II. UBV aperture photometry.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...34S&db_key=AST
|Radio and optical observations of a complete sample of E and S0 galaxies. I - Radial velocities. II - UBV aperture photometry. III - A radio continuum survey at 2.7 and 5.0 GHz|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984AJ.....89...23S&db_key=AST
|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
|Spectroscopic measures of galaxies, their companions, and peculiar galaxies in the southern hemisphere|
Examples of apparent association of galaxies and also of single peculiargalaxies have been drawn from the Catalogue of Southern PeculiarGalaxies and Associations (Arp and Madore, in preparation).Spectroscopic measures are reported for 75 central or peculiar galaxiesand for 97 companion galaxies. Objects are identified by position andillustrated by photographic prints from the UK Schmidt (SRC) survey.Absorption and emission characteristics are tabulated for each spectrum,and heliocentric redshifts are given. The redshifts are calculated to beon the Reference Catalog II system (de Vaucouleurs et al. 1976) towithin plus or minus 50 km/s. The average redshift is repeatable towithin plus or minus 50 km/s. Differential redshifts of objects observedsimultaneously or sequentially can be considerably more accurate.
|Quasars near companion galaxies|
Twenty-two new quasars close to galaxies are reported. All nonellipticalgalaxies brighter than 12.8 with apparent companion galaxies areexamined, and 13 of the 34 candidate companion galaxies are found to bequasars with an accidental probability of less than 0.01. In the RAregion between NGC 5055 and NGC 7448, the confirmation is at the 10 tothe -8th to 10 to the -16th level, and in the NGC 2441 to NGC 3184region, the association is confirmed at the 10 to the -17th to the 10 tothe -19th level. It is concluded that to avoid the association of thesequasars with the low redshift companions, the average background densityof distant quasars must be somewhere around 20 times what it iscurrently measured to be.
Submit a new link
Member of following groups:
Observation and Astrometry data
Catalogs and designations: