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The SCUBA Local Universe Galaxy Survey - III. Dust along the Hubble sequence
We present new results from the Submillimetre Common-User BolometerArray (SCUBA) Local Universe Galaxy Survey (SLUGS), the first largesystematic submillimetre (submm) survey of the local Universe. Since ourinitial survey of a sample of 104 IRAS-selected galaxies we have nowcompleted a survey of a sample of 81 optically selected galaxies,observed with the SCUBA camera on the James Clerk Maxwell Telescope.Since SCUBA is sensitive to the 90 per cent of dust too cold to radiatesignificantly in the IRAS bands our new sample represents the firstunbiased SCUBA survey of dust in galaxies along the whole length of theHubble sequence.We find little change in the properties of dust in galaxies along theHubble sequence, except a marginally significant trend for early-typegalaxies to be less-luminous submm sources than late types. Wenevertheless detected six out of 11 elliptical galaxies, although someof the emission may possibly be synchrotron rather than dust emission.As in our earlier work on IRAS galaxies we find that the IRAS and submmfluxes are well fitted by a two-component dust model with dustemissivity index β= 2. The major difference from our earlier workis that we find the ratio of the mass of cold dust to the mass of warmdust is much higher for our optically selected galaxies and can reachvalues of ~1000. Comparison of the results for the IRAS and opticallyselected samples shows that there is a population of galaxies containinga large proportion of cold dust that is unrepresented in the IRASsample.We derive local submm luminosity and dust mass functions, both directlyfrom our optically selected SLUGS sample, and by extrapolation from theIRAS Point Source Catalogue Redshift Survey (PSCz) survey using themethod of Serjeant and Harrison (by extrapolating the spectral energydistributions of the IRAS PSCz survey galaxies out to 850μm we probea wider range of luminosities than probed directly by the SLUGSsamples), and find excellent agreement between the two. We find them tobe well fitted by Schechter functions except at the highestluminosities. We find that as a consequence of the omission of coldgalaxies from the IRAS sample the luminosity function presented in ourearlier work is too low by a factor of 2, reducing the amount of cosmicevolution required between the low-z and high-z Universe.
| Bar Galaxies and Their Environments
The prints of the Palomar Sky Survey, luminosity classifications, andradial velocities were used to assign all northern Shapley-Ames galaxiesto either (1) field, (2) group, or (3) cluster environments. Thisinformation for 930 galaxies shows no evidence for a dependence of barfrequency on galaxy environment. This suggests that the formation of abar in a disk galaxy is mainly determined by the properties of theparent galaxy, rather than by the characteristics of its environment.
| Rotation curves and metallicity gradients from HII regions in spiral galaxies
In this paper we study long slit spectra in the region of Hαemission line of a sample of 111 spiral galaxies with recognizable andwell defined spiral morphology and with a well determined environmentalstatus, ranging from isolation to non-disruptive interaction withsatellites or companions. The form and properties of the rotation curvesare considered as a function of the isolation degree, morphological typeand luminosity. The line ratios are used to estimate the metallicity ofall the detected HII regions, thus producing a composite metallicityprofile for different types of spirals. We have found that isolatedgalaxies tend to be of later types and lower luminosity than theinteracting galaxies. The outer parts of the rotation curves of isolatedgalaxies tend to be flatter than in interacting galaxies, but they showsimilar relations between global parameters. The scatter of theTully-Fisher relation defined by isolated galaxies is significantlylower than that of interacting galaxies. The [NII]/Hα ratios, usedas a metallicity indicator, show a clear trend between Z andmorphological type, t, with earlier spirals showing higher ratios; thistrend is tighter when instead of t the gradient of the inner rotationcurve, G, is used; no trend is found with the change in interactionstatus. The Z-gradient of the disks depends on the type, being almostflat for early spirals, and increasing for later types. The[NII]/Hα ratios measured for disk HII regions of interactinggalaxies are higher than for normal/isolated objects, even if all thegalaxy families present similar distributions of Hα EquivalentWidth. Tables 3 and 4 and Figs. 6, 7 and 21 are only available inelectronic form at http://www.edpsciences.org. Table 5 is only availablein electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/389 Based on dataobtained Asiago/Ekar Observatory. Also based on observations made withINT operated on the island of La Palma by ING in the SpanishObservatorio del Roque de Los Muchachos of the Instituto deAstrofísica de Canarias.
| The Radio Galaxy Populations of Nearby Northern Abell Clusters
We report on the use of the NRAO VLA Sky Survey (NVSS) to identify radiogalaxies in 18 nearby Abell clusters. The listings extend from the coresof the clusters out to radii of 3 h-175 Mpc, whichcorresponds to 1.5 Abell radii and approximately 4 orders of magnitudein galaxy density. To create a truly useful catalog, we have collectedoptical spectra for nearly all of the galaxies lacking public velocitymeasurements. Consequently, we are able to discriminate between thoseradio galaxies seen in projection on the cluster and those that are inactuality cluster members. The resulting catalog consists of 329 clusterradio galaxies plus 138 galaxies deemed foreground or backgroundobjects, and new velocity measurements are reported for 273 of theseradio galaxies. The motivation for the catalog is the study of galaxyevolution in the cluster environment. The radio luminosity function is apowerful tool in the identification of active galaxies, as it isdominated by star-forming galaxies at intermediate luminosities andactive galactic nuclei (AGNs) at higher luminosities. The flux limit ofthe NVSS allows us to identify AGNs and star-forming galaxies down tostar formation rates less than 1 Msolar yr-1. Thissensitivity, coupled with the all-sky nature of the NVSS, allows us toproduce a catalog of considerable depth and breadth. In addition tothese data, we report detected infrared fluxes and upper limits obtainedfrom IRAS data. It is hoped that this database will prove useful in anumber of potential studies of the effect of environment on galaxyevolution. Based in part on observations obtained with the Apache PointObservatory 3.5 m telescope, which is owned and operated by theAstrophysical Research Consortium (ARC).
| Homogenization of the Stellar Population along Late-Type Spiral Galaxies
We present a study of the broadband UBV color profiles for 257 Sbcbarred and nonbarred galaxies, using photoelectric aperture photometrydata from the literature. Using robust statistical methods, we haveestimated the color gradients of the galaxies, as well as the total andbulge mean colors. A comparative photometric study using CCD images wasdone. In our sample, the color gradients are negative (reddish inward)in approximately 59% of the objects, are almost null in 27%, and arepositive in 14%, considering only the face-on galaxies, which representapproximately 51% of the sample. The results do not change, essentially,when we include the edge-on galaxies. As a consequence of this study wehave also found that barred galaxies are overrepresented among theobjects having null or positive gradients, indicating that bars act as amechanism of homogenization of the stellar population. This effect ismore evident in the U-B color index, although it can also be detected inthe B-V color. A correlation between the total and bulge colors wasfound that is a consequence of an underlying correlation between thecolors of bulges and disks found by other authors. Moreover, the meantotal color is the same irrespective of the gradient regime, whilebulges are bluer in galaxies with null or positive gradients, whichindicates an increase of the star formation rate in the central regionsof these objects. We have also made a quantitative evaluation of theamount of extinction in the center of these galaxies. This was doneusing the Wide Field Planetary Camera 2 (WFPC2) and the Near InfraredCamera and Multi-Object Spectrometer (NICMOS) Hubble Space Telescope(HST) archival data, as well as CCD B, V, and I images. We show thatalthough the extinction in the V-band can reach values up to 2 mag inthe central region, it is unlikely that dust plays a fundamental role inglobal color gradients. We found no correlation between color and O/Habundance gradients. This result could suggest that the color gradientsare more sensitive to the age rather than to the metallicity of thestellar population. However, the absence of this correlation may becaused by dust extinction. We discuss this result by considering apicture in which bars are a relatively fast, recurrent phenomenon. Theseresults are not compatible with a pure classical monolithic scenario forbulge and disk formation. On the contrary, they favor a scenario inwhich both these components are evolving in a correlated process inwhich stellar bars play a crucial role. Based partly on observationsmade at the Pico dos Dias Observatory (PDO/LNA-CNPq), Brazil.
| Investigations of the Local Supercluster velocity field. III. Tracing the backside infall with distance moduli from the direct Tully-Fisher relation
We have extended the discussion of Paper II (Ekholm et al.\cite{Ekholm99a}) to cover also the backside of the Local Supercluster(LSC) by using 96 galaxies within Theta <30degr from the adoptedcentre of LSC and with distance moduli from the direct B-bandTully-Fisher relation. In order to minimize the influence of theMalmquist bias we required log Vmax>2.1 and sigmaB_T<0.2mag. We found out that ifRVirgo<20 Mpc this sample fails to follow the expecteddynamical pattern from the Tolman-Bondi (TB) model. When we compared ourresults with the Virgo core galaxies given by Federspiel et al.(\cite{Federspiel98}) we were able to constrain the distance to Virgo:RVirgo=20-24 Mpc. When analyzing the TB-behaviour of thesample as seen from the origin of the metric as well as that withdistances from the extragalactic Cepheid PL-relation we found additionalsupport to the estimate RVirgo= 21 Mpc given in Paper II.Using a two-component mass-model we found a Virgo mass estimateMVirgo=(1.5 - 2)x Mvirial, whereMvirial=9.375*E14Msun forRVirgo= 21 Mpc. This estimate agrees with the conclusion inPaper I (Teerikorpi et al. \cite{Teerikorpi92}). Our results indicatethat the density distribution of luminous matter is shallower than thatof the total gravitating matter when q0<= 0.5. Thepreferred exponent in the density power law, alpha ~2.5, agrees withrecent theoretical work on the universal density profile of dark matterclustering in an Einstein-deSitter universe (Tittley & Couchman\cite{Tittley99}).
| 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.
| 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).
| Very Wide Galaxy Pairs of the Northern and Southern Sky
We present highly accurate observations of the 21 cm line of hydrogen ingalaxies made at the Arecibo and Parkes Observatories. The galaxiesobserved have been identified, through rigorous selection criteriaapplied to the CfA and SSRS catalogs, as being members of pairs withprojected separations of up to 1.5 Mpc (H0 = 75 km s-1 Mpc-1). Theseobservations form the completion of the Chengalur-Nordgren galaxy pairsample with data previously published by Chengalur, Nordgren andcolleagues. The new selection criteria used in this paper are anextension to larger projected separations of the criteria usedpreviously. Forty-nine new galaxies are observed, while H I is detectedin 41 of them. With the addition of these galaxies, the completed samplehas highly accurate H I velocities for a total of 219 galaxies.
| 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.
| 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.
| 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.
| A study of the large-scale structure in the distribution of galaxies in a region centered about the Cancer cluster. III - Further observational results
Further observational results are presented from a study of thelarge-scale structure in the distribution of galaxies in anapproximately 4000 sq deg region nominally centered about the Cancercluster. The criteria used in defining the galaxy sample and theobservational methods used in its study are reviewed. The H I spectraand the associated measured parameters and derived properties for the134 sample galaxies are presented.
| 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.
| A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
| Inner ring structures in galaxies as distance indicators. III - Distances to 453 spiral and lenticular galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983ApJS...51..149B&db_key=AST
| A radio continuum survey of nearby galaxies. I - Observations at 0.4, 0.8, 4.8, and 10.7 GHz
Observations have been conducted of a total of 136 galaxies at one ormore of four frequencies: 430, 834, 4750, and 10,700 MHz. For a subsetof these, spectral indices could be determined. A mean value alpha =-0.68 + or - 0.04 is found over the whole frequency range covered. Themean high frequency spectral index (4.9-10.7 GHz) for Sc galaxies isalpha = -0.55 + or - 0.07, which indicates the presence of significantamounts of thermal emission in a considerable fraction of the sample. At10.7 GHz the mean thermal contribution to the radio emission of thesample Sc galaxies is 35 + or - 15 percent; for the sample Sb galaxiesthis is 20 + or - 15 percent.
| Flocculent and grand design spiral structure in field, binary and group galaxies
A 12-division morphological system emphasizing arm continuity, lengthand symmetry has been developed for the classification of all spiralgalaxies according to the regularity of their spiral arm structure. Armclassifications were tabulated for 305 barred and nonbarred spiralgalaxies; of these, 79 are isolated, 52 are binary and 174 are ingroups. Among the isolated SA galaxies, 68 + or - 10% have irregular andfragmented, or 'flocculent', spiral structures. Only 32 + or - 10% havesymmetric spiral arms in the classic grand design pattern. Flocculentspirals are the most common structures of galaxies without companions orbars. Since flocculent galaxies may have bars and companions, and granddesign galaxies may have neither bars nor companions, such perturbationsare neither perfectly effective nor always necessary in the driving ofgrand design patterns.
| Radio two-color diagram for QSOs, spiral galaxies, and BL Lac objects
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976AJ.....81..574P&db_key=AST
| Identifications of radio sources with bright galaxies
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1967MNRAS.135..231C&db_key=AST
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