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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.
| Local velocity field from sosie galaxies. I. The Peebles' model
Pratton et al. (1997) showed that the velocity field around clusterscould generate an apparent distortion that appears as tangentialstructures or radial filaments. In the present paper we determine theparameters of the Peebles' model (1976) describing infall of galaxiesonto clusters with the aim of testing quantitatively the amplitude ofthis distortion. The distances are determined from the concept of sosiegalaxies (Paturel 1984) using 21 calibrators for which the distanceswere recently calculated from two independent Cepheid calibrations. Weuse both B and I-band magnitudes. The Spaenhauer diagram method is usedto correct for the Malmquist bias. We give the equations for theconstruction of this diagram. We analyze the apparent Hubble constant indifferent regions around Virgo and obtain simultaneously the Local Groupinfall and the unperturbed Hubble constant. We found:[VLG-infall = 208 ± 9 km s-1] [\log H =1.82 ± 0.04 (H ≈ 66 ± 6 km s-1Mpc-1).] The front side and backside infalls can be seenaround Virgo and Fornax. In the direction of Virgo the comparison ismade with the Peebles' model. We obtain: [vinfall} =CVirgo/r0.9 ± 0.2] withCVirgo=2800 for Virgo and CFornax=1350 for Fornax,with the adopted units (km s-1 and Mpc). We obtain thefollowing mean distance moduli: [μVirgo=31.3 ± 0.2(r=18 Mpc )] [μFornax=31.7 ± 0.3 (r=22 Mpc). ] Allthese quantities form an accurate and coherent system. Full Table 2 isonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/57
| 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
| A Gas-rich Nuclear Bar Fueling a Powerful Central Starburst in NGC 2782
We present evidence that the peculiar interacting starburst galaxy NGC2782 (Arp 215) harbors a gas-rich nuclear stellar bar feeding anM82-class powerful central starburst, from a study based onhigh-resolution interferometric CO (J=1-->0) data and optical BVR andHα observations, along with available near-infrared (NIR) images,a 5 GHz radio continuum map, and archival Hubble Space Telescope (HST)images. Morphological and kinematic data show that NGC 2782 harbors aclumpy, barlike CO feature of radius ~7.5" (1.3 kpc) that leads anuclear stellar bar of similar size. The nuclear barlike CO feature ismassive: it contains ~2.5x109 Msolar of moleculargas, which makes up ~8% of the dynamical mass present within a 1.3 kpcradius. Within the CO bar, emission peaks in two extended clumpy lobesthat lie on opposite sides of the nucleus, separated by ~6" (1 kpc).Between the CO lobes, in the inner 200 pc radius, resides a powerfulcentral starburst that is forming stars at a rate of 3-6Msolar yr-1. While circular motions dominate theCO velocity field, the CO lobes show weak barlike streaming motions onthe leading side of the nuclear stellar bar, suggestive of gas inflow.We estimate semianalytically the gravitational torque from the nuclearstellar bar on the gas and suggest large gas inflow rates from the COlobes into the central starburst. These observations, which are amongthe first ones showing a nuclear stellar bar fueling molecular gas intoan intense central starburst, are consistent with simulations andtheory, which suggest that nuclear bars provide an efficient way oftransporting gas closer to the galactic center to fuel central activity.Furthermore, several massive (107-108Msolar) clumps are present at low radii, and dynamicalfriction might produce further gas inflow. We suggest that the nuclearbarlike molecular gas feature and central activity will be very shortlived, likely disappearing within 5x108 yr.
| An Infrared Search for Extinguished Supernovae in Starburst Galaxies
IR and radio-band observations of heavily extinguished regions instarburst galaxies suggest a high supernova (SN) rate associated withsuch regions. Optically measured SN rates may therefore underestimatethe total SN rate by factors of up to 10, as a result of the very highextinction (A_B~10-20 mag) to core-collapse SNe in starburst regions.The IR/radio SN rates come from a variety of indirect means, however,which suffer from model dependence and other problems. We describe adirect measurement of the SN rate from a regular patrol of starburstgalaxies done with K'-band imaging to minimize the effects ofextinction. A collection of K'-band measurements of core-collapse SNenear maximum light is presented. Such measurements (excluding 1987A) arenot well reported in the literature. Results of a preliminary K'-bandsearch, using the MIRC camera at the Wyoming Infrared Observatory and animproved search strategy using the new ORCA optics, are described. Amonthly patrol of a sample of IRAS bright (mostly starburst) galaxieswithin 25 Mpc should yield 1-6 SNe yr^-1, corresponding to the range ofestimated SN rates. Our initial MIRC search with low resolution (2.2"pixels) failed to find extinguished SNe in the IRAS galaxies, limitingthe SN rate outside the nucleus (at greater than 15" radius) to lessthan 3.8 far-IR SN rate units (SNe per century per 10^10 L_solarmeasured at 60 and 100 mum, or FIRSRU) at 90% confidence. The MIRCcamera had insufficient resolution to search nuclear starburst regions,where starburst and SN activity is concentrated; therefore, we wereunable to rigorously test the hypothesis of high SN rates in heavilyobscured star-forming regions. We conclude that high-resolution nuclearSN searches in starburst galaxies with small fields are more productivethan low-resolution, large-field searches, even for our sample of large(often several arcminutes) galaxies. With our ORCA high-resolutionoptics, we could limit the total SN rate to less than 1.3 FIRSRU at 90%confidence in 3 years of observations, lower than most estimates.
| The I-Band Tully-Fisher Relation for SC Galaxies: 21 Centimeter H I Line Data
A compilation of 21 cm line spectral parameters specifically designedfor application of the Tully-Fisher (TF) distance method is presentedfor 1201 spiral galaxies, primarily field Sc galaxies, for which opticalI-band photometric imaging is also available. New H I line spectra havebeen obtained for 881 galaxies. For an additional 320 galaxies, spectraavailable in a digital archive have been reexamined to allow applicationof a single algorithm for the derivation of the TF velocity widthparameter. A velocity width algorithm is used that provides a robustmeasurement of rotational velocity and permits an estimate of the erroron that width taking into account the effects of instrumental broadeningand signal-to-noise. The digital data are used to establish regressionrelations between measurements of velocity widths using other commonprescriptions so that comparable widths can be derived throughconversion of values published in the literature. The uniform H I linewidths presented here provide the rotational velocity measurement to beused in deriving peculiar velocities via the TF method.
| The I-Band Tully-Fisher Relation for SC Galaxies: Optical Imaging Data
Properties derived from the analysis of photometric I-band imagingobservations are presented for 1727 inclined spiral galaxies, mostly oftypes Sbc and Sc. The reduction, parameter extraction, and errorestimation procedures are discussed in detail. The asymptotic behaviorof the magnitude curve of growth and the radial variation in ellipticityand position angle are used in combination with the linearity of thesurface brightness falloff to fit the disk portion of the profile. TotalI-band magnitudes are calculated by extrapolating the detected surfacebrightness profile to a radius of eight disk scale lengths. Errors inthe magnitudes, typically ~0.04 mag, are dominated by uncertainties inthe sky subtraction and disk-fitting procedures. Comparison is made withthe similar imaging database of Mathewson, Ford, & Buchhorn, both aspresented originally by those authors and after reanalyzing theirdigital reduction files using identical disk-fitting procedures. Directcomparison is made of profile details for 292 galaxies observed incommon. Although some differences occur, good agreement is found,proving that the two data sets can be used in combination with onlyminor accommodation of those differences. The compilation of opticalproperties presented here is optimized for use in applications of theTully-Fisher relation as a secondary distance indicator in studies ofthe local peculiar velocity field.
| 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.
| 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
| Massive Star Formation Along the Hubble Sequence
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....113..599D&db_key=AST
| An Atlas of Hubble Space Telescope Ultraviolet Images of Nearby Galaxies
We present an atlas of UV (~2300 A) images, obtained with the HubbleSpace Telescope (HST) Faint Object Camera, of the central 22" x 22" of110 galaxies. The observed galaxies are an unbiased selectionconstituting about one-half of a complete sample of all large (D >6') and nearby (V < 2000 km s^-1^) galaxies. This is the firstextensive UV imaging survey of normal galaxies. The data are useful forstudying star formation, low-level nuclear activity, and UV emission byevolved stellar populations in galaxies. At the HST resolution (~0.05"),the images display an assortment of morphologies and UV brightnesses.These include bright nuclear point sources, compact young star clustersscattered in the field or arranged in circumnuclear rings, centrallypeaked diffuse light distributions, and galaxies with weak or undetectedUV emission. We measure the integrated ~2300 A flux in each image,classify the UV morphology, and examine trends between these parametersand the optical properties of the galaxies.
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| The bar-enhanced star-formation activities in spiral galaxies.
We use the ratio L_FIR_/L_B_ and the IRAS color index S_25_/S_12_ (bothwidely used as indices of relative star formation rates in galaxies) toanalyse subsets (containing no known AGNs or merging/interactinggalaxies) of: (a) the IRAS Bright Galaxy Sample, (b) galaxies from theoptically complete RSA sample which have IRAS detections in all fourbands, and (c) a volume-limited IR-unselected sample. We confirm thatIR-bright barred (SB) galaxies do, on average, have very significantlyhigher values of the FIR-optical and S_25_/S_12_ ratios (and presumably,higher relative star formation rates, SFR) than that do unbarred ones;the effect is most obvious in the IR colors. We also confirm that thesedifferences are confined to early-type (S0/a-Sbc) spirals and are notevident among late-type systems (Sc-Sdm). Unlike others, we see noenhancement of the SFR in weakly-barred (SAB) galaxies. We furtherconfirm that the effect of bars on the SFR is associated with therelative IR luminosity and show that it is detectable only in galaxieswith L_FIR_/L_B_>1/3, suggesting that as soon as they have anyeffect, bars translate their host galaxies into this relativelyIR-luminous group. Conversely, for galaxies with L_FIR_/L_B_ below ~0.1this luminosity ratio is lower among barred than unbarred systems, againconfirming and quantifying an earlier result. Although there is nosimple physical relation between H I content and star formation, astrong correlation of H I content with the presence of bars has beenfound for early-type spirals with L_FIR_/L_B_>1/3. This suggests thatthe availability of fuel is the factor determining just which galaxiesundergo bar-induced starbursts.
| 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.
| Multiwavelength Energy Distributions and Bolometric Luminosities of the 12 Micron Galaxy Sample
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...453..616S&db_key=AST
| Hubble space telescope observations of young star clusters in NGC-4038/4039, 'the antennae' galaxies
New, high-resolution images of the disks of NGC 4038/4039 obtained withthe Wide Field Camera of the Hubble Space Telescope (HST) are presented.NGC 4038/4039, nicknamed The Antennae, is a prototypical example of apair of colliding galaxies believed to be at an early stage of a merger.Down to the limiting magnitude of V approximately 23 mag, the HST imagesreveal a population of over 700 blue pointlike objects within the disks.The mean absolute magnitude of these objects is MV = -11 mag,with the brightest objects reaching MV approximately -15.Their mean apparent color indices ar U - V = -0.7 mag and V - 1 = 0.8mag on the Johnson UVI passband system, while their mean indicescorrected for internal reddening are (u - v)0 = -1.0 mag and(V - I0 = 0.5. Their mean effective radius, determined fromslightly resolved images, is 18 pc (for H0 = 50 km/s /Mpc).Based on their luminosities and resolution, most of these objects cannotbe individual stars, but are likely young compact star clusters. Thebrighter ones are similar to the objects found in NGC 1275 and NGC 7252,which appear to be young globular clusters formed during recent galazymergers. Based on their U - V and V - I colors, the brightest, bluestclusters of NGC 4038/4039 appear to be less than 10 Myr old. Most ofthese bright clusters are relatively tightly clustered themselves, withtypically a dozen individual clusters belonging to a complex identifiedas a giant H II region from ground-based observations. The clusterluminosity function (LF) is approximately a power law, phi(L)dLproportional to L-1.78+/-0.05dL, with no hint of a turnoverat fainter magnitudes. This power-law shape agrees with the LF ofMagellanic Cloud clusters and Galactic open clusters, but differs fromthe LF of old globular cluster systems that is typically Gaussian with aFull Width at Half Maximum (FWHM) of approximately 3 mag. Besides theblue clusters, we also find about a dozen extremely red objects with V -I greater than 3.0. The highest number density of these red objects isfound in the SE quadrant, where star formation appears to be mostrecent. We propose that these objects may be very young star clustersstill embedded in their placental dust cocoons.
| CO observations of Arp's interacting galaxies
We performed a (C-12)O (J= 1-0) line survey involving fifty fourinteracting galaxies from the Arp's Catalogue of Peculiar Galaxies, andcompared our results with various other data. The far infraredluminosities, as normalized by the CO luminosities, are much greater forinteracting galaxies than for normal galaxies. From correlations withthe interaction class we found that the molecular gas concentration inthe central few kpc is not necessarily enhanced by interaction. However,the efficiency of star formation from the molecular gas increasessignificantly with the interaction class, which results in an apparentincrease in the star-formation rate with the interaction class.
| 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.
| 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.
| Kinematical observations of ordinary spiral galaxies - A bibliographical compilation
Data extracted from 280 papers reporting observations of the kinematicsof 245 nonbarred spiral galaxies are presented. Information is providedon the type of observations (instruments, spectral lines used, etc.) andthe derived geometrical and kinematical parameters of the galaxies(major axis position angle, inclination, heliocentric systemic velocity,maximum extension of the kinematical measurements, etc.). In addition,whenever possible, a 'mean' rotation curve has been considered, fromwhich the maximum rotational velocity of the galaxy and a parameterdescribing the essential shape of the rotation curve within r25 havebeen derived. Histograms illustrating the distribution of morphologicaltypes, inclinations, extensions of the kinematical measurements, andmaximum rotational velocities account for the statistical properties ofthis sample of spiral galaxies.
| A 1.49 GHz atlas of the IRAS Bright Galaxy Sample
The VLA has been used in its A-, B-, C-, and D-configurations to make1.49 GHz maps of sources in both the original and revised IRAS BrightGalaxy Samples of strong extragalactic sources selected at a wavelengthof 60 microns. Integrated 1.49 GHz flux densities were obtained from thelowest resolution maps, and maps were made with higher resolution sothat nearly all of the radio sources have been at least partiallyresolved. Only NGC 1377 was not detected at 1.49 GHz. An atlas ofcontour maps, a table of total flux densities plus other radio sourceparameters, and references to published radio maps are given. Since theinfrared and radio continuum brightness distributions of IR-selectedgalaxies are usually similar, these high-resolution radio maps can beused as substitutes for the unavailable IR maps to indicate the sizesand precise locations of the IR-emitting regions.
| Does the dark component influence the shape of the inner rotation curves of spiral galaxies?
A statistical analysis of the relation between the essential shape ofthe rotation curve, the morphology, and the absolute luminosity ofspiral galaxies is presented for a sample of 167 objects. At variancewith Burstein and Rubin's (1985) results, it is found that the shape ofrotation curves of spirals inside the 'optical' region correlates withthe Hubble type. This fact reflects a correlation between light and massdistributions in the inner galaxian regions, showing that the lineardynamics is not usually controlled by the dark component.
| Gaseous content of galaxies inside groups
The gaseous content of a sample constituted of 84 Sb and 95 Sc galaxiesinside groups has been analyzed. After correcting for the luminosityeffect, no gas deficiency was found for those galaxies in spite of aspan of about 2 orders of magnitude in the galaxy density. Anyintergalactic gas present in the considered groups must have densitiessmaller than 0.0003/cu cm.
| 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 12 micron galaxy sample. I - Luminosity functions and a new complete active galaxy sample
An all-sky 12 micron flux-limited sample of active galaxies was selectedfrom the IRAS Point Source Catalog. Most of the sample galaxies are inexisting catalogs, and 99 percent have measured redshifts. The 12-micronand the far-infrared luminosity functions of active and normal galaxiesare derived using IRAS co-added data. A total of 22 percent of thesample galaxies harbor active nuclei. The sample consists almost equallyof Seyfert 1, Seyfert 2, and LINER nuclei. The derived luminosityfuctions for Seyfert 1 and Seyfert 2 galaxies are indistinguishable fromthose of the optically selected CfA sample. Thus, 12 micron selection isthe most efficient available technique for finding complete activegalaxy samples.
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