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Hα surface photometry of galaxies in nearby clusters
We present the Hα imaging observations of 273 late-type galaxiesin the nearby rich galaxy clusters Virgo, A 1367, Coma, Cancer, Herculesand in the Great Wall, carried out primarily with the 2.1 m telescope ofthe San Pedro Martir Observatory (SPM) and with the ESO/3.6 m telescope.We derived the Hα+[NII] fluxes and equivalent widths. The Hαsurvey reached completion for an optically selected sample of nearbygalaxies in and outside rich clusters. Taking advantage of thecompleteness of the data set, the dependence of Hα properties onthe Hubble type was determined for late-type galaxies in the Virgocluster. Differences in the gaseous content partly account for the largescatter of the Hα EW within each Hubble-type class. We studied theradial distributions of the Hα EW around Coma+A 1367 and the Virgoclusters in two luminosity bins. Luminous galaxies show a decrease intheir average Hα EW in the inner ~1 virial radius, whilelow-luminosity galaxies do not show this trend.
| 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
| Cosmological Results from High-z Supernovae
The High-z Supernova Search Team has discovered and observed eight newsupernovae in the redshift interval z=0.3-1.2. These independentobservations, analyzed by similar but distinct methods, confirm theresults of Riess and Perlmutter and coworkers that supernova luminositydistances imply an accelerating universe. More importantly, they extendthe redshift range of consistently observed Type Ia supernovae (SNe Ia)to z~1, where the signature of cosmological effects has the oppositesign of some plausible systematic effects. Consequently, thesemeasurements not only provide another quantitative confirmation of theimportance of dark energy, but also constitute a powerful qualitativetest for the cosmological origin of cosmic acceleration. We find a ratefor SN Ia of(1.4+/-0.5)×10-4h3Mpc-3yr-1at a mean redshift of 0.5. We present distances and host extinctions for230 SN Ia. These place the following constraints on cosmologicalquantities: if the equation of state parameter of the dark energy isw=-1, then H0t0=0.96+/-0.04, andΩΛ-1.4ΩM=0.35+/-0.14. Includingthe constraint of a flat universe, we findΩM=0.28+/-0.05, independent of any large-scalestructure measurements. Adopting a prior based on the Two Degree Field(2dF) Redshift Survey constraint on ΩM and assuming aflat universe, we find that the equation of state parameter of the darkenergy lies in the range -1.48-1, we obtain w<-0.73 at 95% confidence.These constraints are similar in precision and in value to recentresults reported using the WMAP satellite, also in combination with the2dF Redshift Survey.Based in part on observations with the NASA/ESA Hubble Space Telescope,obtained at the Space Telescope Science Institute, which is operated bythe Association of Universities for Research in Astronomy (AURA), Inc.,under NASA contract NAS 5-26555. This research is primarily associatedwith proposal GO-8177, but also uses and reports results from proposalsGO-7505, 7588, 8641, and 9118.Based in part on observations taken with the Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, le Centre National de la Recherche Scientifique de France, and the University of Hawaii. CTIO: Based in part on observations taken at the Cerro Tololo Inter-American Observatory.Keck: Some of the data presented herein were obtained at the W. M. KeckObservatory, which is operated as a scientific partnership among theCalifornia Institute of Technology, the University of California, and theNational Aeronautics and Space Administration. The Observatory was madepossible by the generous financial support of the W. M. Keck Foundation.UH: Based in part on observations with the University of Hawaii 2.2 mtelescope at Mauna Kea Observatory, Institute for Astronomy, University ofHawaii. UKIRT: Based in part on observations with the United KingdomInfrared Telescope (UKIRT) operated by the Joint Astronomy Centre on behalfof the UK. Particle Physics and Astronomy Research Council. VLT: Based inpart on observations obtained at the European Southern Observatory,Paranal, Chile, under programs ESO 64.O-0391 and ESO 64.O-0404. WIYN: Based in part on observations taken at the WIYN Observatory, a joint facility of the University of Wisconsin-Madison, Indiana University, Yale University, and the National Optical Astronomy Observatories.
| 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 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.
| Kinematics of the Hercules supercluster
The Hercules supercluster consists of the Abell clusters A2147, A2151,and A2152. Previous studies of the kinematics have been confounded bythe difficulty of correctly assigning galaxies to the individualclusters, which are not well separated. Our study has a total of 468available velocities for galaxies in the region, 175 of them new. Thereare 414 galaxies in the supercluster, about three times the number usedin the previous supercluster study. We verify the existence of the threeindividual clusters and compute their individual dynamical parameters.We investigate several techniques for assigning galaxy membership toclusters in this crowded field. We use the KMM mixture-modelingalgorithm to separate the galaxies into clusters; we find that A2152 hasa higher mean velocity than previous studies have reported. A2147 andA2152 also have lower velocity dispersions: 821 and 715 km/s,respectively. The assignment of galaxies to either A2152 or A2147requires velocity and position information. We study the kinematics ofthe supercluster using the two-body formalism of Beers et al. (1982) andconclude that A2147 and A2151 are probably bound to each other and thatthe supercluster as a whole may also be bound. The mass of thesupercluster, if bound, is (7.6 +/- 2.0) 10 exp 15/h M(solar); with thesupercluster luminosity, (1.4 +/- 0.2) 10 exp 13/sq h L(solar), thisyields 0.34 +/- 0.1.
| Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| Galaxies with a UV excess in which supernovae have been observed.
Not Available
| 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.
| Constraining the Ages of Supernova Progenitors. I. Supernovae and Spiral Arms
We present the first results of a three-part study of supernova (SN)ages using positional age indicators in spiral galaxies. We havemeasured the positions of 90 Spectroscopically identified Type Ia andType II SNs (SNs Ia and SNs II) relative to spiral arms in their hostgalaxies, making a special effort to reduce inhomogeneity in the processof arm tracing for different galaxies. We find that SNs II are moretightly concentrated to the arms than SNs Ia, but both kinds of SNsoccur closer to arms than a random disk population. However, whencompared with the distribution of V and I light relative to the arms,the SNs Ia are no more tightly concentrated than the general stellarpopulation. This indicates that SNs Ia occur in a population old enoughto have diffused away from their formation regions.
| Explosion Models for Type IA Supernovae: A Comparison with Observed Light Curves, Distances, H 0, and Q 0
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJ...457..500H&db_key=AST
| Optical and I-band surface photometry of spiral galaxies. I. The data.
We present V- and I-band CCD surface photometry on 234 inclined Sa-Sdgalaxies, completed by similar data in B and R for a reduced subsample.In this first paper of a series, the reduction of the data is discussed,and several comparisons are made with other recent works. Radialprofiles are presented for the surface brightness and thecharacteristics of ellipses fitted to isophotes; global, effective, andisophotal parameters are listed. All the results are available inelectronic form.
| 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.
| Integrated photoelectric magnitudes and color indices of bright galaxies in the Johnson UBV system
The photoelectric total magnitudes and color indices published in theThird Reference Catalogue of Bright Galaxies (RC3) are based on ananalysis of approximately equals 26,000 B, 25,000 B-V, and 17,000 U-Bmultiaperture measurements available up to mid 1987 from nearly 350sources. This paper provides the full details of the analysis andestimates of internal and external errors in the parameters. Thederivation of the parameters is based on techniques described by theVaucouleurs & Corwin (1977) whereby photoelectric multiaperture dataare fitted by mean Hubble-type-dependent curves which describe theintegral of the B-band flux and the typical B-V and U-B integrated colorgradients. A sophisticated analysis of the residuals of thesemeasurements from the curves was made to allow for the random andsystematic errors that effect such data. The result is a homogeneous setof total magnitudes BTA total colors(B-V)T and (U-B)T, and effective colors(B-V)e and (U-B)e for more than 3000 brightgalaxies in RC3.
| A CCD survey of galaxies. IV. Observations with the 2.1 M telescope at San Pedro Martir.
Continuing a CCD survey of galaxies belonging or projected onto the Comaand Hercules Superclusters, to the A262 and Cancer clusters, we presentisophote maps and photometric profiles in the Johnson system of 111galaxies (67 in the V and B bands, 42 only in V, 2 only in B) obtainedwith the 2.1 m telescope at San Pedro Martir (Baja California, Mexico).
| Searching for supernovae--Visually and otherwise
The main features of visual searching for supernovae in other galaxiesby amateur astronomers are described, and an outline is given of theresults which have been achieved so far by this method. A shortcomparison is made between visual searching and photographic searching.A more extensive comparison is then made between visual searching forsupernovae in Australia, and the work of the Berkeley AutomaticSupernova Search at Leuschner Observatory, since 1986. Among theconclusions is the claim that a competent visual observer could producesimilar results to those produced by the Berkeley group if a telescopeof similar aperture was used for a similar amount of observing time, andfrom a good observing site. Indeed, visual searching might possiblyproduce more results, and such a search would only cost a small fractionof what was spent on this automatic search. It would be a worthwhileproject to conduct a visual search with a suitably desinged 76-cmtelescope, or a one metre telescope, over a period of a few years, tosee if this conclusion could be supported in practice.
| A catalog of recent supernovae
A listing is given of all supernovae discovered between 1 Jan 1989 and 1Apr 1993. The data show no evidence for a significant dependence of thediscovery probability of supernovae on parent galaxy inclination to theline of sight. If no inclination corrections need to be applied then thesupernova rates in spirals are only about half as large as previouslybelieved. The mean linear separation of supernovae of Type II (SNe II)from the center of their parent galaxy increases with increasingdistance (Shaw effect). The Shaw effect appears less evident, or absent,for (more luminous) supernovae of Type Ia. The data are consistent with,but do not prove, the hypothesis that (presumably reddended) SNe II aremore likely to be discovered in the red than in the blue. Due tointensive surveillance, most bright SNe Ia tend to be found beforemaximum, whereas the majority of faint SNe Ia are discovered aftermaximum light.
| Arm structure in normal spiral galaxies, 1: Multivariate data for 492 galaxies
Multivariate data have been collected as part of an effort to develop anew classification system for spiral galaxies, one which is notnecessarily based on subjective morphological properties. A sample of492 moderately bright northern Sa and Sc spirals was chosen for futurestatistical analysis. New observations were made at 20 and 21 cm; thelatter data are described in detail here. Infrared Astronomy Satellite(IRAS) fluxes were obtained from archival data. Finally, new estimatesof arm pattern radomness and of local environmental harshness werecompiled for most sample objects.
| Galaxy structures in the Hercules region
216 redshifts have been obtained in a region of 981 sq deg south of theHercules supercluster. 172 of these redshifts are of galaxies withmpg less than or equal to 15.1, 110 of which had no previousvelocity measurement. 44 new redshifts are of galaxies fainter thanmpg = 15.1. With these new data we have been able to define asample in a vast region (approximately 1700 sq deg) around Herculeslimited to mpg less than or equal to 15.1 with a velocitycompleteness of 81.5%. 189 galaxies have been morphologically classifiedso that all galaxies in the sample with known velocity now also haveknown morphology. The magnitude limited sample, including 556 galaxies,is then used to identify and describe galaxy structures in the region.We find that the overdense volume is small, that its overall appearanceis that of a coral branch floating in a sea of nothing and that earlyand late type galaxies defined different structures.
| CCD photometry of three Type IA supernovae - V, R, and I light curves
Attention is given to Cousins system VRI photometry obtained for theType Ia supernova 1992G with CCDs attached to small telescopes atLeuschner Observatory, Van Vleck Observatory (VVO), and WhitinObservatory. Two other Type Ia supernovae, 1991M and 1991T, wereobserved only at VVO. The I template shows a secondary maximum 23 +/- 1d after the primary peak, similar to what is seen in normal Type Iasupernovae at J, H, and K wavelengths. The behavior in R is intermediatebetween V and I. The observed colors of SN 1991M and SN1991T as afunction of time are quite similar, indicating that they suffer aboutthe same amount of reddening. If Type Ia supernovae are assumed to begood standard candles, then NGC 4527, the parent galaxy of SN 1991T,must have a peculiar velocity of 1200 +/- 150 km/s relative to theHubble flow and directed away from the galaxy. If the peculiar velocityof NGC 4527 is less than this, then SN 1991T must be an overluminous SNIa.
| High rate for Type IC supernovae
Using an automated telescope, 20 SNe in carefully documentedobservations of nearby galaxies were detected. The SN rates for latespiral (Sbc, Sc, Scd, and Sd) galaxies, normalized to a blue luminosityof 10 exp 10 are 0.4, 1.6, and 1.1 h squared per 100 years for Types Ia,Ic, and II SNe. The rate for Type Ic SNe is significantly higher thanfound in previous surveys. The rates are not corrected for detectioninefficiencies and do not take into account the indications that the IcSNe are fainter on the average than the previous estimates; thereforethe true rates are probably higher. The rates are not strongly dependenton the galaxy inclination, in contradiction to previous compilations. Ifthe Milky Way is a late spiral, then the rate of the Galactic SNe isgreater than 1 per 30 +/-7 yr, assuming h = 0.75. This high rate hasencouraging consequences for future neutrino and gravitational waveobservatories.
| A survey of small-scale extremes in extinction at low Galactic latitudes using IRAS galaxies
Optical CCD and 21 cm H I data are combined here via the Tully-Fisherrelation to study the Galactic extinction in the V an I bands over anangular scale of a few arcmin at absolute Galactic latitudes between 2and 16 deg. Extinctions in V and I bands are found to be linearlycorrelated with A(I) about 0.58 A(V), with no noticeable environmentaldependence and consistent with existing results of Galactic reddening.There is a large scatter in the simple linear relation with csc /b/,confirming the existence of 'holes' and patches at low Galacticlatitudes. The mean correlation between Galactic extinction and H Icolumn density over a comparable angular scale is also found to beconsistent with those at high latitudes over large angular scales.Correlation is also found between optical extinction and the IRAS 100micron sky brightness, and this sky brightness is only slightly worsethan H I column density as an indicator for optical extinction.
| 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.
| The far-infrared properties of the CfA galaxy sample. I - The catalog
IRAS flux densities are presented for all galaxies in the Center forAstrophysics magnitude-limited sample (mB not greater than 14.5)detected in the IRAS Faint Source Survey (FSS), a total of 1544galaxies. The detection rate in the FSS is slightly larger than in thePSC for the long-wavelength 60- and 100-micron bands, but improves by afactor of about 3 or more for the short wavelength 12- and 25-micronbands. This optically selected sample consists of galaxies which are, onaverage, much less IR-active than galaxies in IR-selected samples. Itpossesses accurate and complete redshift, morphological, and magnitudeinformation, along with observations at other wavelengths.
| The Distance to the Hercules Supercluster. II. Application of Tertiary Indicators and an Estimate of the Hubble Constant
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986ApJS...62..283B&db_key=AST
| The distance to the Hercules supercluster. I - Basic data for 220 galaxies in CGCG field 108.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986ApJS...62..255B&db_key=AST
| High signal-to-noise ratio observations of H I in 243 galaxies
The 21 cm spectral-line system of the Arecibo Observatory was used tomeasure neutral hydrogen emission from 243 faint galaxies. Most lie nearthe plane of the Local Supercluster. All observations reach anunsmoothed signal-to-noise ratio of at least 7.0; the average for theset is 23. The resulting data are used to estimate H I masses, systemicvelocities, and accurate profile widths at 20 percent, 25 percent, 50percent, and 80 percent of peak intensity levels. The widths are used tocalibrate directly the bias introduced by popular data-smoothingoperation. The data include observations of 65 objects with previouslyunknown redshifts.
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