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Gas and Stars in an H I-Selected Galaxy Sample
We present the results of a J-band study of the H I-selected AreciboDual-Beam Survey and Arecibo Slice Survey galaxy samples using TwoMicron All Sky Survey data. We find that these galaxies span a widerange of stellar and gas properties. However, despite the diversitywithin the samples, we find a very tight correlation between luminosityand size in the J band, similar to that found in a previous paper byRosenberg & Schneider between the H I mass and size. We also findthat the correlation between the baryonic mass and the J-band diameteris even tighter than that between the baryonic mass and the rotationalvelocity.
| The Rotation Curves of Dwarf Galaxies: A Problem for Cold Dark Matter?
We address the issue of accuracy in recovering density profiles fromobservations of rotation curves of galaxies. We ``observe'' and analyzeour models in much the same way as observers do the real galaxies. Ourmodels include stellar disks, disks with bars, and small bulges. We findthat the tilted-ring model analysis produces an underestimate of thecentral rotational velocity. In some cases the galaxy halo densityprofile seems to have a flat core, while in reality it does not. Weidentify three effects that explain the systematic biases: inclination,small bulge, and bar. Inclination effects are due to the finitethickness of the disk, bar, or bulge. Admixture of a nonrotating bulgecomponent reduces the rotational velocity. A small (200-500 pc) bulgemay be overlooked, leading to systematic bias even on relatively large(~1 kpc) distances. In the case of a disk with a bar, the underestimateof the circular velocity is larger because of a combination ofnoncircular motions and random velocities. The effect of the bar dependson the angle that the bar makes with the line of sight. Signatures ofbars can be difficult to detect in the surface brightness profiles ofthe model galaxies. The variations of inclination angle and isophoteposition angle with radius are more reliable indicators of bar presencethan the surface brightness profiles. The systematic biases in thecentral ~1 kpc of galaxies are not large. Each effect separately givestypically a few km s-1 error, but the effects add up. In somecases the error in circular velocity was a factor of 2, but typically weget about a 20% effect. The result is the false inference that thedensity profile of the halo flattens in the central parts. Ourobservations of real galaxies show that for a large fraction of galaxiesthe velocity of gas rotation (as measured by emission lines) is veryclose to the rotation of the stellar component (as measured byabsorption lines). This implies that the systematic effects discussed inthis paper are also applicable both for the stars and emission-line gas.
| The ISOPHOT 170 μm Serendipity Survey II. The catalog of optically identified galaxies%
The ISOPHOT Serendipity Sky Survey strip-scanning measurements covering≈15% of the far-infrared (FIR) sky at 170 μm were searched forcompact sources associated with optically identified galaxies. CompactSerendipity Survey sources with a high signal-to-noise ratio in at leasttwo ISOPHOT C200 detector pixels were selected that have a positionalassociation with a galaxy identification in the NED and/or Simbaddatabases and a galaxy counterpart visible on the Digitized Sky Surveyplates. A catalog with 170 μm fluxes for more than 1900 galaxies hasbeen established, 200 of which were measured several times. The faintest170 μm fluxes reach values just below 0.5 Jy, while the brightest,already somewhat extended galaxies have fluxes up to ≈600 Jy. For thevast majority of listed galaxies, the 170 μm fluxes were measured forthe first time. While most of the galaxies are spirals, about 70 of thesources are classified as ellipticals or lenticulars. This is the onlycurrently available large-scale galaxy catalog containing a sufficientnumber of sources with 170 μm fluxes to allow further statisticalstudies of various FIR properties.Based on observations with ISO, an ESA project with instruments fundedby ESA Member States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.Members of the Consortium on the ISOPHOT Serendipity Survey (CISS) areMPIA Heidelberg, ESA ISO SOC Villafranca, AIP Potsdam, IPAC Pasadena,Imperial College London.Full Table 4 and Table 6 are only available in electronic form at theCDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/422/39
| A Survey for H2O Megamasers. III. Monitoring Water Vapor Masers in Active Galaxies
We present single-dish monitoring of the spectra of 13 extragalacticwater megamasers taken over a period of 9 years and a single epoch ofsensitive spectra for seven others. The primary motivation is a searchfor drifting line velocities analogous to those of the systemic featuresin NGC 4258, which are known to result from centripetal acceleration ofgas in an edge-on, subparsec molecular disk. We detect a velocity driftanalogous to that in NGC 4258 in only one source, NGC 2639. Another, themaser source in NGC 1052, exhibits erratic changes in its broad maserprofile over time. Narrow maser features in all of the other diskgalaxies discussed here either remain essentially constant in velocityover the monitoring period or are sufficiently weak or variable inintensity that individual features cannot be traced reliably from oneepoch to the next. In the context of a circumnuclear, molecular diskmodel, our results suggest that either (a) the maser lines seen aresystemic features subject to a much smaller acceleration than present inNGC 4258, presumably because the gas is farther from the nuclear blackhole, or (b) we are detecting ``satellite'' lines for which theacceleration is in the plane of the sky.Our data include the first K-band science observations taken with thenew 100 m Green Bank Telescope (GBT). The GBT data were taken duringtesting and commissioning of several new components and so are subjectto some limitations; nevertheless, they are in most cases the mostsensitive H2O spectra ever taken for each source and cover800 MHz (~=10,800 km s-1) of bandwidth. Many new maserfeatures are detected in these observations. Our data also include atentative and a clear detection of the megamaser in NGC 6240 at epochs ayear and a few months, respectively, prior to the detections reported byHagiwara et al. and Nakai et al.We also report a search for water vapor masers toward the nuclei of 58highly inclined (i>80deg), nearby galaxies. These sourceswere selected to investigate the tendency that H2O megamasersfavor inclined galaxies. None were detected, confirming that megamasersare associated exclusively with active galactic nuclei.
| An H I/Optical Atlas of Isolated Galaxies
We present an H I and optical survey of 41 extremely isolated galaxiesin an attempt to search for the gaseous remnants of the galaxy formationprocess, predicted to exist by hierarchical models of galaxy formation.By observing extremely isolated, quiescent, nonpeculiar galaxies weminimize the chances that any extragalactic H I found will be anothergalaxy, tidal debris, or ejecta from a galactic fountain or superwind.We have obtained new and archival data from the VLA and ATCA in a searchfor H I clouds down to MHI~107 Msolararound these galaxies. We found 13 H I-rich companions around 10 of the41 galaxies surveyed. Optical imaging finds spatially coincident starsassociated with all 13 companions. We find that the isolated galaxieshave properties fairly similar to those of field galaxies, while thecompanions are similar to dwarf irregular galaxies. The presence ofstars in all 13 companions suggests that H I clouds without starsdiscovered by other authors around field galaxies are not primordial andmost likely have either a tidal or ejecta origin.
| The Arecibo Dual-Beam Survey: Arecibo and VLA Observations
The Arecibo Dual-Beam Survey is a ``blind'' 21 cm search for galaxiescovering ~430 deg2 of sky. We present the data from thedetection survey as well as from the follow-up observations to confirmdetections and improve positions and flux measurements. We find 265galaxies, many of which are extremely low surface brightness. Some ofthese previously uncataloged galaxies lie within the zone of avoidance,where they are obscured by the gas and dust in our Galaxy. Eighty-one ofthese sources are not previously cataloged optically, and there are 11galaxies that have no associated optical counterpart or are onlytentatively associated with faint wisps of nebulosity on the DigitizedSky Survey images. We discuss the properties of the survey, and inparticular we make direct determinations of the completeness andreliability of the sample. The behavior of the completeness and itsdependencies is essential for determining the H I mass function. Weleave the discussion of the mass function for a later paper, but do notethat we find many low surface brightness galaxies and seven sources withMHI<108 Msolar. The AreciboObservatory is part of the National Astronomy and Ionosphere Center,which is operated by Cornell University under cooperative agreement withthe National Science Foundation. in Puerto Rico.
| 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.
| Correlations among Global Photometric Properties of Disk Galaxies
Using a two-dimensional galaxy image decomposition technique, we extractglobal bulge and disk parameters for a complete sample of early-typedisk galaxies in the near-infrared K band. We find significantcorrelation of the bulge parameter n with the central bulge surfacebrightness μb(0) and with effective radiusre. Using bivariate analysis techniques, we findthat logn, logre, and μb(0) are distributed ina plane with small scatter. We do not find a strong correlation of nwith bulge-to-disk luminosity ratio, contrary to earlier reports. Forthese early-type disk galaxies, re and the diskscale length rd are well correlated, but withlarge scatter. We examine the implications of our results for variousbulge formation scenarios in disk galaxies.
| 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 ISOPHOT 170 μ m serendipity survey. I. Compact sources with galaxy associations
The first set of compact sources observed in the ISOPHOT 170 μmSerendipity Survey is presented. From the slew data with low(I100 μm <= 15 MJy/sr) cirrus background, 115well-observed sources with a high signal-to-noise ratio in all detectorpixels having a galaxy association were extracted. Of the galaxies withknown optical morphologies, the vast majority are classified as spirals,barred spirals, or irregulars. The 170 μm fluxes measured from theSerendipity slews have been put on an absolute flux level by usingcalibration sources observed additionally with the photometric mappingmode of ISOPHOT. For all but a few galaxies, the 170 μm fluxes aredetermined for the first time, which represents a significant increasein the number of galaxies with measured Far-Infrared (FIR) fluxes beyondthe IRAS 100 μm limit. The 170 μm fluxes cover the range 2 <~F170 μm la 100 Jy. Formulae for the integrated FIR fluxesF40-220μm and the total infrared fluxesF1-1000μm incorporating the new 170 μm fluxes areprovided. The large fraction of sources with a high F170μm / F100 μm flux ratio indicates that a cold(TDust la 20 K) dust component is present in many galaxies.The detection of such a cold dust component is crucial for thedetermination of the total dust mass in galaxies, and, in cases with alarge F170 μm / F100 μm flux ratio,increases the dust mass by a significant factor. The typical mass of thecoldest dust component is MDust = 107.5 +/- 0.5Msun , a factor 2-10 larger than that derived from IRASfluxes alone. As a consequence, the majority of the derived gas-to-dustratios are much closer to the canonical value of ~ 160 for the MilkyWay. By relaxing the selection criteria, it is expected that theSerendipity Survey will eventually lead to a catalog of 170 μm fluxesfor ~ 1000 galaxies. Based on observations with ISO, an ESA project withinstruments funded by ESA Member States (especially the PI countries:France, Germany, the Netherlands and the United Kingdom) and with theparticipation of ISAS and NASA. Members of the Consortium on the ISOPHOTSerendipity Survey (CISS) are MPIA Heidelberg, ESA ISO SOC Villafranca,AIP Potsdam, IPAC Pasadena, Imperial College London.
| Arcsecond Positions of UGC Galaxies
We present accurate B1950 and J2000 positions for all confirmed galaxiesin the Uppsala General Catalog (UGC). The positions were measuredvisually from Digitized Sky Survey images with rms uncertaintiesσ<=[(1.2")2+(θ/100)2]1/2,where θ is the major-axis diameter. We compared each galaxymeasured with the original UGC description to ensure high reliability.The full position list is available in the electronic version only.
| Near-infrared surface photometry of bulges and disks of spiral galaxies. The data
We present optical and near-infrared (NIR) surface brightness and colourprofiles, in bands ranging from U to K, for the disk and bulgecomponents of a complete sample of 30 nearby S0 to Sbc galaxies withinclinations larger than 50 deg. We describe in detail the observationsand the determination of colour parameters. Calibrated monochromatic andreal-colour images are presented, as well as colour index maps. Thisdata set, tailored for the study of the population characteristics ofgalaxy bulges, provides useful information on the colours of inner disksas well. In related papers, we have used them to quantify colourgradients in bulges, and age differentials between bulge and inner disk.
| Large-Scale Structure at Low Galactic Latitude
We have extended the CfA Redshift Survey to low galactic latitudes toinvestigate the relation between the Great Wall in the North GalacticCap and the Perseus-Pisces chain in the South Galactic Cap. We presentredshifts for 2020 galaxies in the Catalogue of Galaxies and of Clustersof Galaxies (Zwicky et al. 1961-68, CGCG) in the following regions: 4^h^<= α <= 8^h^, 17^h^ <= α <= 20^h^, 0^deg^ <=δ <= 45^deg^. In these regions, the redshift catalogue includes1664 galaxies with B(0) <= 15.5 (of which 820 are newly measured) andis 97% complete. We also include redshifts for an additional 356galaxies in these regions with B(O) > 15.5; of these, 148 werepreviously unmeasured. The CGCG samples the galaxy distribution down tob_II_ = 10^deg^. In this paper, we discuss the acquisition and reductionof the spectra, and we examine the qualitative features of the redshiftdistribution. The Great Wall and the Perseus-Pisces chain are not simplyconnected across the Zone of Avoidance. These structures, which at firstappear to be coherent on scales of ~100 h^-1^ Mpc or more, actually formthe boundaries of neighboring voids of considerably smaller scale,approximately 50h^-1^ Mpc. The structures delineated by ouroptically-selected sample are qualitatively similar to those detected bythe far-infrared-selected IRAS 1.2 Jansky Survey (Fisher et al. 1995).Although the IRAS survey probes more deeply into the Zone of Avoidance,our optically-selected survey provides better sampling of structures atb_II_ >= 10^deg^.
| Ages of Galaxies Bulges and Disks From Optical and Near-Infrared Colors
We compare optical and near-infrared colors of disks and bulges in adiameter-limited sample of inclined, bright, nearby, early-type spirals.Color profiles along wedge apertures at 15^deg^ from the major axis andon the minor axis on the side of the galaxy opposite to the dust laneare used to assign nominal colors for the inner disks (at 2 scalelength) and for the bulges (~0.5r_eff_), respectively. We estimate thatthe effects of dust reddening and the cross-talk between the colors ofthe two components is negligible. We find that color differences(bulge-disk) are very small: {DELTA}(U-R) = 0.126+/-0.165,{DELTA}(R-K)=0078+/-0.165. Disks tend to be bluer by an amount threetimes smaller than that reported by Bothun & Gregg [ApJ,350,73(1990)] for S0s. Color variations from galaxy to galaxy are muchlarger than color differences between disk and bulge in each galaxy.Probably, the underlying old population of disks and bulges is much moresimilar than the population paradigm would lead us to believe. Impliedage differences, assuming identical metallicities, are less than 30%.
| The Shape of the Luminosity Profiles of Bulges of Spiral Galaxies
Using a 2D generalization of Kent's model-independent decompositionmethod, we extract the K-band light profiles of the bulges of a sampleof field galaxies with morphological types ranging from S0 to Sbc. Wethen examine the shape of the bulge profiles, by means of fitting aseeing-convolved power law of the form μ(r) is proportional tor^1/n^, where the exponent n is allowed to vary. The best-fittingexponent n is found to vary systematically from values around 1(exponential) to 6 from late- to early- type bulges; the profiles tendto fall off more steeply in the outer parts for the later types. Thesame trend is seen as a function of bulge to disc ratio. Application ofthe method to artificial data proves that this result is not caused bydisc-light contamination. There are also indications that n becomeslarger with increasing total luminosity and radius of the bulge. Asimilar relation has recently been found for elliptical galaxies. Thesmooth trend of n with morphological type shows that the formation of orinteraction with the disc has affected the density distribution of thebulge.
| 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.
| Colors and color gradients in bulges of galaxies
We have obtained surface photometry in U, B, R, and I for a completeoptically selected sample of 45 early-type spiral galaxies, toinvestigate the colors and color gradients of spiral bulges. Colorprofiles in U-R, B-R, U-B, and R-I have been determined in wedgesopening on the semiminor axes. Based on several criteria, like thesmoothness of the color profiles, the absence of dust lanes, and thecentral colors, we have defined a subsample of 18 objects whose colorsare largely unaffected by dust. We believe such colors are suitable forinferring properties of the stellar populations of bulges. We find thatthe colors of bulges are predominantly bluer than those of ellipticals.This result holds even when bulges are compared to ellipticals of thesame luminosity, and indicates that bulges are younger and/or more metalpoor than old elliptical galaxies. Most bulges do not reach solarmetallicities. Bulges show predominantly negative color gradients (blueroutward). For bright bulges (MBulgeR is less than-20.0), the magnitude of the gradient increases with bulge luminosity.For fainter bulges, gradients scatter around large negative values. Thebehavior of color gradients as a function of bulge luminosity suggestsdifferent formation mechanisms for faint and bright spheroids. Forbright bulges, the scaling of gradients with luminosity suggests aformation process involving dissipation. The similarity with ellipticalssuggests that the formation of the disk did not affect the stellarpopulations of the bulge in a major way. For small bulges (MRis greater than -20), the existence of pronounced color gradientssuggests a different formation mechanism. For these objects, thepresence of the disk may have severely affected the radial populationdistribution in the bulge.
| Satellites of spiral galaxies
We present a survey of satellites around a homogeneous set of late-typespirals with luminosity similar to that of the Milky Way. On average, wefind fewer than 1.5 satellites per primary, but we argue that we cantreat the survey as an ensemble and so derive the properties of the haloof a 'typical' isolated spiral. The projected density profile of theensemble falls off approximately as 1/r. Within 50 kpc the azimuthaldistribution of satellites shows some evidence for the 'Holmbergeffect', an excess near the minor axis of the primary; however, atlarger projected distances, the distribution appears isotropic. There isa weak but significant correlation between the size of a satellite andits distance from its primary, as expected if satellites are tidallytruncated. Neither Hubble type nor spectral characteristics correlatewith apparent separation. The ensemble of satellites appears to berotating at about 30 km/s in the same direction as the galactic disk.Satellites on prograde orbits tend to be brighter than those onretrograde orbits. The typical velocity difference between a satelliteand its primary shows no clear dependence either on apparent separation,or on the rotation speed of the primary. Thus our survey demonstratesthat isolated spiral galaxies have massive halos that extend to manyoptical radii.
| Nearby galaxy flows modeled by the light distribution - Distances, model, and the local velocity anomaly
Tables giving measured galaxy distances used to construct a map ofobserved peculiar velocities, and giving a grid of the distribution oflight used to construct a map of expected peculiar velocities arepresented. A preferred model was developed which yielded a best fitbetween these maps, and this model was used to generate output kinematicdistances which are recorded for groups and individual galaxies withV0 of less than 3000 km/s. In terms of the ratio ofpeculiar-to-systemic velocities, the local velocity anomaly is the mostimportant perturbation involving substantial numbers of galaxies forthis case. The ratio of these quantities in this case is larger than forthe more famous cases of the Virgocentric or Great Attractorperturbations. Maps which illustrate the fit of the present mass modelto the velocity data in the local region are provided. A graphicaldemonstration of the relative importance of large-scale streaming tolocal motions within the context of this model is presented.
| Axial ratios of edge-on spirals
A diameter-limited sample of 888 normal Sa-Sc galaxies was compiled fromthe Uppsala General Catalog. New micrometer measures of the axial ratiosR of the disk components of 262 edge-on spirals in this sample were madeon copies of blue Palomar Sky Survey plates and calibrated againstphotometric standards. The distribution of isophotal axial ratios forthe whole sample was analyzed to give information on the true axialratios R0 of spiral disks. The mean value of logR0 is 0.95 +/- 0.03 and the dispersion about this mean is0.12 +/- 0.04. A similar mean value (0.90) was obtained from avolume-limited sub-sample of 348 spirals. The dispersion in logR0 is partly due to a dependence of R0 onmorphological type, and the mean value of log R0 for eachtype was estimated. Inclinations of 342 edge-on (R is greater than about3) spirals were determined from their isophotal axial ratios and types.No significant dependence of R0 on luminosity at each typewas found.
| 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 peculiar velocity of the Local Group. I - H I observations of SB and SBC galaxies
H I observations of a sample of 128 Sb and Sbc galaxies ranging inlinear diameter from 9-128 kpc, and in total mass from 6.3 x 10 to the9th solar masses to 1.3 x 10 to the 12th solar masses, are presented.Measurements of H I self-absorption are not found to vary withinclination, though a dependence of observed diameters and luminositieson inclination is noted. Total surface mass density and color index areshown to be highly correlated, implying that star-formation in thesegalaxies is governed by disk density rather than total mass or gasrichness. From 12-arcmin resolution local Galactic H I observations, newcorrection factors for diameters and luminosities are derived to allowfor the effects of galactic obscuration.
| H I line studies of galaxies. IV - Distance moduli of 468 disk galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1985A&AS...59...43B&db_key=AST
| A catalog of infrared magnitudes and H I velocity widths for nearby galaxies
Integrated infrared (1.6 micron) magnitudes and 21 cm velocity widthsare presented for 308 nearby spiral galaxies. Positions, types,inclinations, diameters, H I velocities and flux density integrals, anddistances are also listed. These data form the basis for a recentanalysis of the velocity field in the Local supercluster.
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