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|The Photometric and Kinematic Structure of Face-on Disk Galaxies. I. Sample Definition, Hα Integral Field Spectroscopy, and H I Line Widths|
We present a survey of the photometric and kinematic properties of 39nearby, nearly face-on disk galaxies. Our approach exploitsechelle-resolution integral-field spectroscopy of the Hα regions,obtained with DensePak on the WIYN 3.5 m telescope Bench Spectrograph.These data are complemented by H I line profiles observed with theNançay radio telescope for 25 of these sample galaxies. Twelveadditional line widths are available for sample galaxies from theliterature. In this paper, we introduce the goals of this survey, definethe sample selection algorithm, and amass the integral fieldspectroscopic data and H I line widths. We establish spatiallyintegrated Hα line widths for the sample. We test the veracity ofthese spatially integrated line profiles by convolving narrowbandimaging data with velocity field information for one of the samplegalaxies, PGC 38268, and also by comparing to H I line profiles. We findH I and Hα line profiles to be similar in width but different inshape, indicating that we are observing different spatial distributionsof ionized and neutral gas in largely axisymmetric systems with flatouter rotation curves. We also find vertical velocity dispersions of theionized disk gas within several disk scale lengths have a median valueof 18 km s-1 and an 80% range of 12-26 km s-1.This is only a factor of ~2 larger than what is observed for neutralatomic and molecular gas. With standard assumptions for intrinsic andthermal broadening for Hα, this translates into a factor of 3range in turbulent velocities, between 8 and 25 km s-1.
|A Face-on Tully-Fisher Relation|
We construct the first ``face-on'' Tully-Fisher (TF) relation for 24galaxies with inclinations between 16° and 41°. The enablingmeasurements are integral-field echelle spectroscopy from the WIYN 3.5 mtelescope, which yield accurate kinematic estimates of disk inclinationto ~15°. Kinematic inclinations are of sufficient accuracy that ourmeasured TF scatter of 0.42 mag is comparable to other surveys evenwithout internal absorption corrections. Three of four galaxies withsignificant kinematic and photometric asymmetries also have the largestdeviations from our TF relation, suggesting that asymmetries make animportant contribution to TF scatter. By measuring inclinations below40°, we establish a direct path to linking this scatter to theunprojected structure of disks and making nondegenerate dynamical massdecompositions of spiral galaxies.
|Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies|
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
|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.
|21 CM H1 Line Spectra of Galaxies in Nearby Clusters|
A compilation of HI line fluxes, systemic velocities and line widths ispresented for \Ndet detected galaxies, mostly in the vicinities of 30nearby rich clusters out to a redshift of z ~ .04, specifically for usein applications of the Tully-Fisher distance method. New 21 cm HI lineprofiles have been obtained for ~ 500 galaxies in 27 Abell clustersvisible from Arecibo. Upper limits are also presented for \Nnod galaxiesfor which HI emission was not detected. In order to provide ahomogeneous line width determination optimized for Tully-Fisher studies,these new data are supplemented by the reanalysis of previouslypublished spectra obtained both at Arecibo and Green Bank that areavailable in a digital archive. Corrections for instrumental broadening,smoothing, signal-to-noise and profile shape are applied, and anestimate of the error on the width is given. When corrected forturbulent broadening and viewing angle, the corrected velocity widthspresented here will provide the appropriate line width parameter neededto derive distances via the Tully-Fisher relation.
|An image database. II. Catalogue between δ=-30deg and δ=70deg.|
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
|Cluster population incompleteness bias and the value of H(0) from the Tully-Fisher B0(T) relation|
Data on the Virgo cluster and ten more distant clusters are the basis ofan evaluation of the influence of the cluster population incompletenessbias on the B-band Tully-Fisher relation. The data are well fitted by atheoretical curve that is obtained for a Hubble constant value of 72 +or - 5 km/sec per Mpc in the de Vaucouleurs local scale, confirming theconstant's previous determination in light of a study of the Malmquistbias for field galaxies. The true value for the Hubble constant isconcluded to lie within the 50-75 range, depending on the primarycalibration.
|KISO survey for ultraviolet-excess galaxies. IV|
Presented here are the fourth list and identification charts of theultraviolet-excess galaxies which have been detected on the multicolorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of some 300 square degrees 752 objects are cataloged downto the photographic magnitude of about 18.
|A catalog of radio, optical, and infrared observations of spiral galaxies in clusters|
The results of a major observational program on the luminosities,colors, and gas contents of spiral galaxies in clusters of galaxies arepresented. The data have been used as part of a detailed investigationinto the nature of cluster spirals and for revisions of the distancescale using the infrared Tully-Fisher relation. The observationalstrategies, reduction procedures, and sources or error are brieflydiscussed. The data include 21-cm H I observations, UBVR multiaperturephotometry, and H-band photometry of several hunderd spiral galaxies in10 clusters.
|The Cancer Cluster - an unbound collection of groups|
A surface density contour map of the Cancer Cluster derived from galaxycounts in the Zwicky catalog is presented. The contour map shows thatthe galaxy distribution is clumpy. When this spatial distribution iscombined with nearly complete velocity information, the clumps stand outmore clearly; there are significant differences in the mean velocitiesof the clumps which exceed their internal velocity dispersions. TheCancer Cluster is not a proper 'cluster' but is a collection of discretegroups, each with a velocity dispersion of approximately 300 km/s,separating from one another with the cosmological flow. Themass-to-light ratio for galaxies in the main concentration isapproximately 320 solar masses/solar luminosities (H0 = 100km/s Mpc).
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