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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.
| 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
| The QDOT all-sky IRAS galaxy redshift survey
We describe the construction of the QDOT survey, which is publiclyavailable from an anonymous FTP account. The catalogue consists ofinfrared properties and redshifts of an all-sky sample of 2387 IRASgalaxies brighter than the IRAS PSC 60-μm completeness limit(S_60>0.6Jy), sparsely sampled at a rate of one-in-six. At |b|>10deg, after removing a small number of Galactic sources, the redshiftcompleteness is better than 98per cent (2086/2127). New redshifts for1401 IRAS sources were obtained to complete the catalogue; themeasurement and reduction of these are described, and the new redshiftstabulated here. We also tabulate all sources at |b|>10 deg with noredshift so far, and sources with conflicting alternative redshiftseither from our own work, or from published velocities. A list of 95ultraluminous galaxies (i.e. with L_60μm>10^12 L_solar) is alsoprovided. Of these, ~20per cent are AGN of some kind; the broad-lineobjects typically show strong Feii emission. Since the publication ofthe first QDOT papers, there have been several hundred velocity changes:some velocities are new, some QDOT velocities have been replaced by moreaccurate values, and some errors have been corrected. We also present anew analysis of the accuracy and linearity of IRAS 60-μm fluxes. Wefind that the flux uncertainties are well described by a combination of0.05-Jy fixed size uncertainty and 8per cent fractional uncertainty.This is not enough to cause the large Malmquist-type errors in the rateof evolution postulated by Fisher et al. We do, however, find marginalevidence for non-linearity in the PSC 60-μm flux scale, in the sensethat faint sources may have fluxes overestimated by about 5per centcompared with bright sources. We update some of the previous scientificanalyses to assess the changes. The main new results are as follows. (1)The luminosity function is very well determined overall but is uncertainby a factor of several at the very highest luminosities(L_60μm>5x10^12L_solar), as this is where the remainingunidentified objects are almost certainly concentrated. (2) Thebest-fitting rate of evolution is somewhat lower than our previousestimate; expressed as pure density evolution with density varying as(1+z)^p, we find p=5.6+/-2.3. Making a rough correction for the possible(but very uncertain) non-linearity of fluxes, we find p=4.5+/-2.3. (3)The dipole amplitude decreases a little, and the implied value of thedensity parameter, assuming that IRAS galaxies trace the mass, isΩ=0.9(+0.45, -0.25). (4) Finally, the estimate of density varianceon large scales changes negligibly, still indicating a significantdiscrepancy from the predictions of simple cold dark matter cosmogonies.
| 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
| Homogeneous Velocity-Distance Data for Peculiar Velocity Analysis. III. The Mark III Catalog of Galaxy Peculiar Velocities
This is the third in a series of papers in which we assemble and analyzea homogeneous catalog of peculiar velocity data. In Papers I and II, wedescribed the Tully-Fisher (TF) redshift-distance samples thatconstitute the bulk of the catalog and our methodology for obtainingmutually consistent TF calibrations for these samples. In this paper, wesupply further technical details of the treatment of the data andpresent a subset of the catalog in tabular form. The full catalog, knownas the Mark III Catalog of Galaxy Peculiar Velocities, is available inaccessible on-line databases, as described herein. The electroniccatalog incorporates not only the TF samples discussed in Papers I andII but also elliptical galaxy Dn- sigma samples originally presentedelsewhere. The relative zero pointing of the elliptical and spiral datasets is discussed here. The basic elements of the Mark III Catalog arethe observables for each object (redshift, magnitude, velocity width,etc.) and inferred distances derived from the TF or Dn- sigma relations.Distances obtained from both the forward and inverse TF relations aretabulated for the spirals. Malmquist bias--corrected distances arecomputed for each catalog object using density fields obtained from theIRAS 1.2 Jy redshift survey. Distances for both individual objects andgroups are provided. A variety of auxiliary data, including distancesand local densities predicted from the IRAS redshift surveyreconstruction method, are tabulated as well. We study the distributionsof TF residuals for three of our samples and conclude that they are wellapproximated as Gaussian. However, for the Mathewson et al. sample wedemonstrate a significant decrease in TF scatter with increasingvelocity width. We test for, but find no evidence of, a correlationbetween TF residuals and galaxy morphology. Finally, we derivetransformations that map the apparent magnitude and velocity width datafor each spiral sample onto a common system. This permits theapplication of analysis methods that assume that a unique TF relationdescribes the entire sample.
| Optical Rotation Curves and Linewidths for Tully-Fisher Applications
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2402C&db_key=AST
| The I band Tully-Fisher relation for cluster galaxies: data presentation.
Observational parameters which can be used for redshift-independentdistance determination using the Tully-Fisher (TF) technique are givenfor \ntot spiral galaxies in the fields of 24 clusters or groups. I bandphotometry for the full sample was either obtained by us or compiledfrom published literature. Rotational velocities are derived either from21 cm spectra or optical emission line long-slit spectra, and convertedto a homogeneous scale. In addition to presenting the data, a discussionof the various sources of error on TF parameters is introduced, and thecriteria for the assignment of membership to each cluster are given.
| 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.
| A 1.425 GHz Atlas of the IRAS Bright Galaxy Sample, Part II
Galaxies with δ >= -45^deg^ and |b| >= 10^deg^ in the IRASBright Galaxy Sample, Part II, were observed at 1.425 GHz by the VeryLarge Array in its B, CnB, C, DnC, and D configurations. An atlas ofradio contour maps and a table listing the principal radio sourceparameters (position, flux density, angular size) are given. This atlasof 187 galaxies supplements the 1.49 GHz atlas of 313 galaxies in therevised Bright Galaxy Sample, Part I. Together, they are complete forextragalactic sources stronger than S = 5.24Jy at λ = 60 micronsin the area |b| > 10^deg^, δ > -45^deg^. To the extent thatthe far-infrared and radio brightness distributions overlap, these radiomaps provide the most accurate positions and high-resolution images ofthe brightest extragalactic far-infrared sources.
| Rotation Curves of 967 Spiral Galaxies
We present the rotation curves of 967 southern spiral galaxies, obtainedby deprojecting and folding the raw Hα data originally publishedby Mathewson, Ford, & Buchhorn (1992). For 900 objects, we alsopresent, in figures and tables, the rotation curves smoothed on scalescorresponding to 5%-20% of the optical size; of these, 80 meet objectiveexcellence criteria and are suitable for individual detailed massmodeling, while 820, individually less compelling mainly because of themoderate statistics and/or limited extension, are suitable forstatistical studies. The remaining 67 curves suffer from severeasymmetries, small statistics, and large internal scatter that maylargely limit their use in galaxy structure studies. The deprojectedfolded curves, the smoothed curves, and various related quantities areavailable via anonymous ftp at galileo.sissa.it in the directory/users/ftp/pub/psrot.
| Recalibration of the H-0.5 magnitudes of spiral galaxies
The H-magnitude aperture data published by the Aaronson et al.collaboration over a 10 year period is collected into a homogeneous dataset of 1731 observations of 665 galaxies. Ninety-six percent of thesegalaxies have isophotal diameters and axial ratios determined by theThird Reference Cataloque of Bright Galaxies (RC3; de Vaucouleurs et al.1991), the most self-consistent set of optical data currently available.The precepts governing the optical data in the RC3 are systematicallydifferent from those of the Second Reference Catalogue (de Vaucouleurs,de Vaucouleurs, & Corwin 1976), which were used by Aaronson et al.for their original analyses of galaxy peculiar motions. This in turnleads to systematic differences in growth curves and fiducialH-magnitudes, prompting the present recalibration of the near-infraredTully-Fisher relationship. New optically normalized H-magnitude growthcurves are defined for galaxies of types SO to Im, from which new valuesof fiducial H-magnitudes, Hg-0.5, are measured forthe 665 galaxies. A series of internal tests show that these fourstandard growth curves are defined to an accuracy of 0.05 mag over theinterval -1.5 less than or equal to log (A/Dg) less than orequal to -0.2. Comparisons with the Aaronson et al. values of diameters,axial ratios, and fiducial H-magnitudes show the expected differences,given the different definitions of these parameters. The values ofHg-0.5 are assigned quality indices: a qualityvalue of 1 indicates an accuracy of less than 0.2 mag, quality 2indicates an accuracy of 0.2-0.35 mag, and quality 3 indicates anaccuracy of more than 0.35 mag. Revised values of corrected H I velocitywidths are also given, based on the new set of axial ratios defiend bythe RC3.
| The IRAS Bright Galaxy Survey - Part II: Extension to Southern Declinations (delta ~< -30), and Low Galactic Latitudes (f<|b|
Complete IRAS Observations and redshifts are reported for all sourcesidentified in the IRAS Bright Galaxy Survey-Part II (hereafter referredto as BGS_2_). Source positions, radial velocities, optical magnitudes,and total flux densities, peak flux densities, and spatial extents at12, 25, and 100 ,microns are reported for 288 sources having 60 micronflux densities > 5.24 Jy, the completeness limit of the originalBright Galaxy Survey [Soifer et al., AJ, 98,766(1989)], hereafterreferred to as BGS_1_. These new data represent the extension of theIRAS Bright Galaxy Survey to southern declinations,δ<~-30^deg^, and low Galactic latitudes,5^deg^<|b|<30^deg^. Although the sky coverage of the BGS_2_ (~19935 deg^2^) is 37% larger than the sky coverage of the BGS_1_, thenumber of sources is 8% smaller due primarily to large scale structurein the local distribution of galaxies. Otherwise, the sources in theBGS_2_ show similar relationships between number counts and flux densityas observed for the 313 sources in the BGS_1_. The BGS_2_ along with theearlier BGS, represents the best sample currently available for definingthe infrared properties of galaxies in the local (z <~ 0.1) Universe.
| 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.
| Astrophysical gasdynamics confronts reality - The shaping of planetary nebulae
We present two-dimensional numerical simulations, which use techniquesof radiation gasdynamics to simulate the structures of planetary nebulae(PNs). Our model incorporates realistic volume emissivities in order tofully account for the conversion of mechanical and thermal energy intoradiation. The model also produces detailed predictions of observablessuch as projected structure (e.g., H-alpha and forbidden N II images)and kinematic patterns. Virtually the full range of PN morphologies areeasily reproduced, as are the basic kinematics, ionization structures,and temperatures.
| 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 southern sky survey of the peculiar velocities of 1355 spiral galaxies
The paper presents data from photometric and spectroscopic observationsof 1355 southern spiral galaxies and uses them to determine theirdistances and peculiar velocities via the Tully-Fisher (TF) relation.I-band CCD surface photometry was carried out using the 1-m and 3.9-mtelescopes at Siding Spring Observatory. H-alpha rotation curves for 965galaxies and 551 H I profiles are presented. The physical parameters,photometric and velocity data, distances, and peculiar velocities of thegalaxies are presented in tabular form. The mean distance, systemicvelocity, and average peculiar velocity of 24 clusters in the sample aregiven. TF diagrams are presented for each cluster.
| I-band CCD surface photometry of spiral galaxies in 16 nearby clusters
Results of I-band CCD surface photometry for 284 spiral galaxies in 16clusters in the redshift range from 3000 to 11,000 km/s are presented.Various effects on surface photometry are discussed, and the relevantcorrections are outlined.
| Anomalously high intercombination line ratios in symbiotic stars - Extreme Bowen pumping?
International Ultraviolet Explorer observations of the ratio of the OIII intercombination lines near 1660 A are assembled, showing that theobserved ratios in symbiotic stars are significantly higher than thetheoretically predicted optically thin limit of 2.5. The presence of anenhancing physical process is thereby indicated. It is suggested thatBowen pumping of the lower level of the 1666.2 A line in an 'externalsaturation' limit, coupled with appreciable optical depth, couldlogically explain the high ratios. Some tentative evidence for this ispresented and the relevance of far-infrared observations of the O III51.8 and 88.3 micron lines in symbiotic sources is emphasized.
| Large peculiar velocities in the Hydra-Centaurus supercluster
Distances from the infrared Tully-Fisher relation have been obtainedwith the Parkes radio telescope for six clusters of galaxies in theHydra-Centaurus supercluster. Three of these clusters show significantpositive peculiar velocities of order 500 km/s in a comoving referenceframe in which the observer is at rest with respect to the cosmicmicrowave background radiation. The net peculiar velocity of the samplesuggests that Hydra-Centaurus tends to share the motion of the LocalGroup in this reference frame. The data also fit a model in which twomass concentrations, one at Virgo and one just beyond the centroid ofthe Parkes sample, perturb the Hubble flow.
| The temperatures of the nuclei of high-excitation planetary nebulae
An empirical relationship between the ratio of the intensities of theemission lines 4686 He II/H-beta and N1 + N2 forbidden O III/4868 He IIin the spectra of planetary nebulae is proposed. Upper and lower limitsfor the nucleus temperature have been obtained for 97 planetary nebulae.A new quantitative system for the determination of the excitationclasses of nebulae has been derived.
| 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.
| Southern Galaxy Catalogue.
Not Available
| Apparent magnitudes of luminous planetary nebula nuclei. I Method and application
The paper presents new B- and/or V-magnitudes for the nuclei of 51planetary nebulae, as well as limits for 10 others, from absolutephotometry with the University of Illinois 1 m telescope, and a superiormethod of extracting stellar continuum fluxes from a bright nebularbackground. The errors and the limitations of the method are carefullyexamined. The results are compared with the widely circulated list ofpreliminary central-star magnitudes determined by Shao and Liller, whichare shown to suffer frequently from severe contamination from thenebular continuum, and a calibration is provided for older photographicmagnitudes. Finally, the nebular contribution to the continuum in thecontext of the evolution of central stars on the log L-log T plane isexamined, and the implications for future observations of hot and/oryoung planetary nuclei are discussed.
| H I line studies of galaxies. III - Distance moduli of 822 disk galaxies
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
| The Connection Between the Geometry Kinematics of the Gaseous Clouds and the Shape of the Emission Line Profiles in the Active Nuclei of Galaxies and Quasars - Diagnostic Ability of Rapid Variations of the Line Profiles
Not Available
| Near-infrared spectrophotometry of planetary nebulae
An IR spectrophotometric study of 10 planetary nebulae in whichstrengths were measured for the Paschen lines Pa-beta and Pa-gamma, theforbidden S III lines 9069 and 9532 A, and He I 10830 A, yields lineflux determinations indicating that excess continuum flux at 1.28microns for five of the planetary nebulae is of central star origin. Thecentral star radiation can be appreciable at 1.65 microns, whereexcesses found previously have been linked to radiation from hot dust. Adiscrepancy is noted between the measured ratio of the 10830 and 5876 AHe triplet line fluxes and previously predicted values, though agreementbetween predicted and observed ratios is obtained with a model in whichthe dust optical depth, and therefore the attenuation of resonantlyscattered 10830 A photons, decreases with nebular expansion.
| 21-cm line profiles of 392 spiral galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982A&AS...50..101B&db_key=AST
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