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|The IRAS Revised Bright Galaxy Sample|
IRAS flux densities, redshifts, and infrared luminosities are reportedfor all sources identified in the IRAS Revised Bright Galaxy Sample(RBGS), a complete flux-limited survey of all extragalactic objects withtotal 60 μm flux density greater than 5.24 Jy, covering the entiresky surveyed by IRAS at Galactic latitudes |b|>5°. The RBGS includes629 objects, with median and mean sample redshifts of 0.0082 and 0.0126,respectively, and a maximum redshift of 0.0876. The RBGS supersedes theprevious two-part IRAS Bright Galaxy Samples(BGS1+BGS2), which were compiled before the final(Pass 3) calibration of the IRAS Level 1 Archive in 1990 May. The RBGSalso makes use of more accurate and consistent automated methods tomeasure the flux of objects with extended emission. The RBGS contains 39objects that were not present in the BGS1+BGS2,and 28 objects from the BGS1+BGS2 have beendropped from RBGS because their revised 60 μm flux densities are notgreater than 5.24 Jy. Comparison of revised flux measurements forsources in both surveys shows that most flux differences are in therange ~5%-25%, although some faint sources at 12 and 25 μm differ byas much as a factor of 2. Basic properties of the RBGS sources aresummarized, including estimated total infrared luminosities, as well asupdates to cross identifications with sources from optical galaxycatalogs established using the NASA/IPAC Extragalactic Database. Inaddition, an atlas of images from the Digitized Sky Survey with overlaysof the IRAS position uncertainty ellipse and annotated scale bars isprovided for ease in visualizing the optical morphology in context withthe angular and metric size of each object. The revised bolometricinfrared luminosity function, φ(Lir), forinfrared-bright galaxies in the local universe remains best fit by adouble power law, φ(L)~Lα, withα=-0.6(+/-0.1) and α=-2.2(+/-0.1) below and above the``characteristic'' infrared luminosityL*ir~1010.5Lsolar,respectively. A companion paper provides IRAS High Resolution (HIRES)processing of over 100 RBGS sources where improved spatial resolutionoften provides better IRAS source positions or allows for deconvolutionof close galaxy pairs.
|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.
|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.
|Investigation of Barred Galaxies. V. Surroundings of SB and SA Galaxies|
|Lopsidedness in Early-Type Disk Galaxies|
We quantify the mean asymmetry of 54 face-on, early-type disk galaxies(S0 to Sab) using the amplitude of the m = 1 azimuthal Fourier componentof the R-band surface brightness. We find that the median lopsidedness,, of our sample is 0.11 and that the most lopsided 20% ofour galaxies have >= 0.19. Asymmetries in early-typedisks appear to be of similar frequency and strength as in late-typedisk galaxies. We have observed our early-type disks in a bandpass (Rband) in which the light is dominated by stars with ages greater than10^9 yr and therefore are seeing azimuthal asymmetries in the stellarmass distribution. The similar degree of lopsidedness seen in disks ofvery different star formation rates indicates that the lopsidedness inall galactic disks is primarily due to azimuthal mass asymmetries.Hence, 20% of all disk galaxies (regardless of Hubble type) haveazimuthal asymmetries, >= 0.19, in their stellar diskmass distribution, confirming lopsidedness as a dynamical phenomenon.
|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.
|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 188.8.131.52. 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.
|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.
|A Preliminary Classification Scheme for the Central Regions of Late-Type Galaxies|
The large-scale prints in The Carnegie Atlas of Galaxies have been usedto formulate a classification scheme for the central regions oflate-type galaxies. Systems that exhibit small bright central bulges ordisks (type CB) are found to be of earlier Hubble type and of higherluminosity than galaxies that do not contain nuclei (type NN). Galaxiescontaining nuclear bars, or exhibiting central regions that are resolvedinto individual stars and knots, and galaxies with semistellar nuclei,are seen to have characteristics that are intermediate between those oftypes CB and NN. The presence or absence of a nucleus appears to be auseful criterion for distinguishing between spiral galaxies andmagellanic irregulars.
|The nuclear 10 micron emission of spiral galaxies|
We examine the 10 micrometer(s) emission of the central regions of 281spiral galaxies, after having compiled all ground-based, small-aperture(approximately 5 sec) broad-band photometric observations at lambdaapproximately 10 micrometer(s) (N magnitudes) published in theliterature. We evaluate the compactness of the approximately 10micrometer(s) emission of galaxy nuclei by comparing these small-beammeasures with the large-beam IRAS 12 micrometer(s) fluxes. In theanalysis of different subsets of objects, we apply survival analysistechniques in order to exploit the information contained in 'censored'data (i.e., upper limits on the fluxes). Seyfert galaxies are found tocontain the most powerful nuclear sources of mid-infrared emission,which in approximately one-third of the cases provide the bulk of theemission of the entire galaxy; thus, mid-infrared emission in the outerdisk regions is not uncommon in Seyfert galaxies. The 10 micrometer(s)emission of Seyfert galaxies appears to be unrelated to their X-rayemission. H II region-like nuclei are stronger mid-infrared sources thannormal nuclei and LINER nuclei (whose level of emission is notdistinguishable form that of normal nuclei). Interacting objects have,on average, greater 10 micrometer(s) luminosities than noninteractingones and exhibit more compact emission. Early-type spirals have strongerand more compact 10 micrometer(s) emisison than late-type ones. Barredspirals are brighter at approximately 10 micrometer(s) than unbarredsystems, essentially because they more frequently contain H IIretion-like nuclei. The results of our detailed comparison between thebehavior of various categories of objects stress that the 10micrometer(s) emission of spiral nuclei is closely linked to the(predominantly nonthermal synchrotron) radio emission.
|UBVRI photoelectric photometry of bright southern early-type galaxies|
UBVRI multi-aperture photometry of 207 bright southern galaxies and of72 objects of an additional list is presented. These observations weremade for obtaining the magnitude scale zero-point as an accuratedetermination of the sky background for a two-dimensional photometryprogram concerning these galaxies. We have also inferred the asymptoticmagnitudes, color indices and effective apertures of these objects. Ourresults are in good agreement with those of others authors.
|The extended 12 micron galaxy sample|
We have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns.
|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.
|Far infrared radiation from elliptical galaxies|
Infrared radiation for 35 nearby elliptical galaxies is analyzed and IRfluxes at 12, 25, 60, and 100 microns are investigated. It is shown thatthe radiation at a wavelength of 60-100 microns belongs to cold dustwith a color temperature of 25-45 K located in the nuclei of galaxieswith a diameter of several kpc. The radiation at a wavelength of 12-25microns with a color temperature of 150-260 K may belong either to thedust concentrated near compact sources in the galactic center (a starcluster or a black hole) or to the dust in the envelopes of low-masscold giants.
|Nearby starburst galaxies|
New multiaperture 1.65 and 2.2 micron photometry has been obtained forthe central region of 132 spirals exhibiting 2 orders of magnitude rangein central 10-micron luminosity. This multiaperture photometry alongwith optical spectroscopy indicated that the high central 10-micronluminosity (about 1 billion solar luminosities) is powered by massivestar formation for the majority of the sample objects. The large database has led to the definition of a complete sample of nearby M82-typestarburst galaxies, the majority of which have not previously beenrecognized as such. Observation results and comparison with starburstmodels support the interpretation that, as in the case of M82, redsupergiants dominate the central 2.2-micron luminosity of the starburstsin this sample. The starburst galaxy M82 is anomalous in comparison withthe starburst galaxies identified in this study, by virtue of a rarehigh central 2.2-micron luminosity.
|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.
|Uncertainties in 21 centimeter redshifts. I - Data|
High-precision data on the 21-cm redshifts, profile widths, and shapesfor 625 galaxies are presented. Each galaxy is listed in across-identification and morphology table. High-resolution spectra arealso given for each galaxy. Internal redshift consistency is roughly 1km/s for galaxies for which the S/N is above 15. No systematic effectshave been found which might influence the observed redshift quantizationat 72.5 km/s or its submultiples.
|The spatial distribution of 10 micron luminosity in spiral galaxies|
The present ground-based 10-micron observations of 133 nearby luminous,noninteracting IR galaxies indicate that about 40 percent of theearly-type barred spirals are associated with enhanced 10-micronluminosity in the central (about 1-kpc diameter) region. The luminositysource may be either Seyfert activity or star formation, or both. Thedifference in bar-central luminosity association in early- and late-typespirals indicates that the bulge/disk ratio may be an importantparameter in the determination of central IR luminosity in barredspirals.
|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.
|H I observations of galaxies in between the Local and the Hydra/Centaurus superclusters|
H I observations obtained with the 300-ft NRAO and 100-m Effelsbergradio telescopes in 1984-1985 are reported for 440 galaxies, ofmorphological types S0/a or later and diameter at least 2 arcmin in thecatalog of de Vaucouleurs et al., 1976, from the region between theLocal and Hya/Cen superclusters. The data are compiled in tables alongwith published data on 310 galaxies to form a data base for studies offilamentary structures in the intercluster region. More than 50 percentof the galaxies are detected in H I, and the redshift distribution isfound to be consistent with the existence of filaments.
|The H I content of lenticular and early-type galaxies - A comparison between field and Virgo cluster samples|
A very simple method to take into account the upper limits of detectionis used to study and discuss the distribution of the H I contents of 122lenticular galaxies. The results show the Virgo cluster S0s to be H Ideficient when compared to the noncluster ones, and the H I contents ofthe latter to be about five times lower than the ones of the S0/aspirals and to increase along the de Vaucouleurs sequence of types -3 to-1. It is shown that the early spirals in Virgo are H I-deficient by afactor higher than 10, i.e., they have no more gas than noncluster S0s.It is argued that noncluster S0s have a primordial origin, and that asubstantial proportion of Virgo S0s come from stripped early spirals.
|Study of the Nuclei of NGC3732 and IC4662|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1981ApJ...244...27P&db_key=AST
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