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Dark matter in the inner parts of barred galaxies: The data
This paper presents surface photometry (B,V,I,J,H,K) and Hαrotation curves of 27 isolated spiral galaxies. The final goal is toobtain the mass distribution of a sample of isolated spiral galaxies inorder to model their gas kinematics. This is then compared to theobserved rotation curve, to determine the necessity of a dark halo inthe inner parts (Perez et al. 2004, A&A, 424, 799). The azimuthallyaveraged radial surface brightness profiles and the integratedmagnitudes obtained from ellipse fitting are given for each of thesample galaxies. The ellipse fitting technique applied to the lightdistribution also allowed us to obtain the size of the bar, and theinclination and position angle of the outer isophotes that allow thegalaxy deprojection. Using these profiles, 1-D disk-bulge decompositionwas performed to obtain the disk scale-length and the bulge effectiveradius for the different bands. Through the fitting of a parametricfunction to the observed rotation curve, the maximum rotational velocityand the corresponding radius was obtained. The correlation between thebulge and disk parameters is in agreement with previous studies (de Jong1996a, A&A, 313, 45; Márquez & Moles 1999, A&A, 344,421; Baggett et al. 1998, AJ, 116, 1626). Regarding the Kormendyrelation (Kormendy 1977, ApJ, 218, 333), in agreement with de Jong, nocorrelation between the bulge effective radius and its surfacebrightness is found, possibly due to the small range of bulge magnitudescovered. We find a smaller scatter in the structural relations whencompared to non-isolated samples in agreement with Márquez &Moles (1999). Finally, a correlation between the disk scale-length andthe bar size is observed, possibly reflecting the rapid growth of a bar.
| Gas flow and dark matter in the inner parts of early-type barred galaxies. I. SPH simulations and comparison with the observed kinematics
This paper presents the dynamical simulations run in the potentialderived from the light distribution of 5 late-type barred spiralgalaxies (IC 5186, NGC 5728,NGC 7267, NGC 7483 and NGC 5505). The aim is to determine whether the massdistribution together with the hydrodynamical simulations can reproducethe observed line-of-sight velocity curves and the gas morphology in theinner regions of these barred galaxies. The light distribution isobtained from the H-band and the I-band combined. The M/L is determinedusing population synthesis models. The observations and the methodologyof the mass distribution modelling are presented in a companion paper.The SPH models using the stellar mass models obtained directly from theH-band light distributions give a good representation of the gasdistribution and dynamics of the modelled galaxies, supporting themaximum disk assumption. This result indicates that the gravitationalfield in the inner region is mostly provided by the stellar luminouscomponent. When 40% of the total mass is transferred to an axisymmetricdark halo, the modelled kinematics clearly depart from the observedkinematics, whereas the departures are negligible for dark mass halos of5% and 20% of the total mass. This result sets a lower limit for thecontribution of the luminous component of about 80%, which is inagreement with the maximum disk definition of the stellar masscontribution to the rotation curve (about 85% ± 10). This resultis in agreement with the results found by \citet{weiner01} forNGC 4123 using a similar methodology. For twogalaxies, NGC 7483 and IC 5186, a very good agreement with the observeddata is found. In these cases the non-circular motions can help to breakthe disk-halo degeneracy. For the other three galaxies (NGC 5728, NGC7267 and NGC 5505) no definite results are found: for NGC 7267 and NGC5505 no steady state is reached in the simulations and for NGC 5728there is no good agreement with the observed kinematics, possibly due tothe presence of a secondary bar decoupled from the primary. However, forthis latter galaxy the M/L ratio used gives the right amplitude of therotation curve, in further support of the M/L calculation method usedthroughout this work. Fast bars give the best fit to the observedkinematics for NGC 7483 and IC 5186 with corotation at the end of thebar for NGC 7483 and at 1.4× Rbar for IC 5186. For NGC5505 for which no steady state configuration is found, the addition of arigid halo stabilises the gas flows but the derived kinematics does notfit well the observations.Figures \ref{fig:vel1}-\ref{fig:Lz_IC5186}, \ref{fig:mask_height},\ref{fig:height_rc}, \ref{fig:rc_NGC5728}, \ref{fig:pv_NGC7483},\ref{fig:substract_NGC7483}, \ref{fig:mask_dm}, \ref{fig:dm_rc} and\ref{fig:ngc5505_dm_rc} are only available in electronic form athttp://www.edpsciences.org}
| 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
| Analysis of the distribution of HII regions in external galaxies. IV. The new galaxy sample. Position and inclination angles
We have compiled a new sample of galaxies with published catalogs of HIIregion coordinates. This sample, together with the former catalog ofGarcía-Gómez & Athanassoula (\cite{gga1}), will formthe basis for subsequent studies of the spiral structure in discgalaxies. In this paper we address the problem of the deprojection ofthe galaxy images. For this purpose we use two deprojection methodsbased on the HII region distribution and compare the results with thevalues found in the literature using other deprojection methods. Takinginto account the results of all the methods, we propose optimum valuesfor the position and inclination angles of all the galaxies in oursample. Tables 2 and 3 are only available in electronic form athttp://www.edpsciences.org
| Environmental effects in galaxies. Molecular gas, star formation, and activity
In order to study whether there is any correlation between nuclearactivities, gas content, and the environment where galaxies reside, wehave obtained optical and millimetric spectra for a well-defined sampleof intermediate Hubble type spirals in dense environments and in thefield. We found that these spirals in dense environments have onaverage: less molecular gas per blue luminosity, a higher atomic gasfraction, lower current star formation rate, and the same star formationefficiency as field galaxies. Although none of these results stands outas a single strong diagnostic given their statistical significance,taken together they indicate a trend for diminished gas content andstar-formation activity in galaxies in high-density environments. Ourresults suggest that galaxies in dense environments have either (i)consumed their molecular gas via star formation in the past or (ii) thatdense environments leads to an inhibition of molecular gas from atomicphase. The similarities in star-formation efficiency of the denseenvironments and field galaxies suggest that the physical processescontroling the formation of stars from the molecular gas are localrather than global. We also found that star formation rate per blueluminosity increases linearly as the total amount of gas increases inLINERs. This result, based on a small sample, suggests that LINERs arepowered by star formation rather than an AGN. Based on observations atthe European Southern Observatory at the 15 m Swedish ESO Submillimetretelescope, SEST, and at the the 1.52 m telescope which is operated underthe ESO-ON agreement.
| Environmental effects in galaxies. The data{
We present optical and millimetric data for 47 intermediate Hubble typespiral galaxies located either in dense environments or in the field. Wecompare correlations between global parameters, such as far-infraredluminosity, blue luminosity, and total molecular gas content, with othersamples of galaxies, including normal galaxies, clusters andultraluminous infrared galaxies. We find that overall our sample is awell-defined subset of these other samples of galaxies. Based onobservations at the European Southern Observatory at the 15 m SwedishESO Submillimetre telescope, SEST, and at the the 1.52 m telescope whichis operated under the ESO-ON agreement. Appendix A is only available inelectronic form at http://www.edpsciences.org
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| 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.
| The Montreal Blue Galaxy Survey.III.Third List of UV-Bright Candidates
We present and discuss the latest addition of the Montreal Blue Galaxy(MBG) survey. Inspection of 59 Curtis Schmidt plates resulted in theidentification of 135 new UV-bright galaxies with B < 15.5. Thisbrings the total number of MBGs to 469. New results of the V/V_m testshow that our survey is complete to B = 14.7. From our most recentspectroscopic follow-up, we confirm the discovery of one new Seyfert 1galaxy and possibly one new Seyfert 2 galaxy. We confirm also the biasof the MBG survey towards the low-excitation and metal rich StarburstNucleus Galaxies (SBNGs). The spectral characteristics of the MBGs aresimilar to those of the infrared luminous IRAS galaxies. As a commoncharacteristic, they show a mean ratio Log([NII]/Hα ) in excess of0.2 dex as compared to normal disk HII regions. In general, the MBGshave lower far-infrared luminosities (LIR < 10(11)Lsun) and are nearer (z < 0.05) than the luminous IRASgalaxies. The distribution of the morphologies of the MBGs indicates ahigh number of early-type spirals (Sb and earlier). Nearly half of thesegalaxies also possess a bar. In our sample, the fraction of galaxieswith bars depends on the morphology and increases towards the late-typespirals. However, if we consider only isolated galaxies, the late-typespirals show a clear tendency to be barred. Signs of a recentinteraction with neighbor galaxies are obvious only in 24% of ourcandidates. Although this number is only a lower limit, it isnevertheless sufficiently low to suggest that in a majority of massivegalaxies the burst of star formation do not depends solely on dynamicalprocesses.
| The Distribution and Properties of H II Regions in Early-to-Intermediate Hubble Type Ringed Galaxies
This paper presents a study of the H II regions in 32 ringed andpseudo-ringed galaxies having Hubble types in the range S0 + to Sc. Theobjective is to illustrate the distributions of H II regions in classicexamples of ringed galaxies and to relate the observed properties toresonance theory. The sample is selected from the Catalog of SouthernRinged Galaxies and includes examples covering a range of ring andgalaxy morphological properties. We find that the distribution ofHα luminosity around inner rings is sensitive to the intrinsicshape of the rings. Extremely oval inner rings show a greaterconcentration of H II regions near the intrinsic ring major axiscompared to more circular rings. Nuclear rings are present in several ofthe sample galaxies and show a range of morphological properties, from adouble nuclear ring in NGC 1317 to an irregular feature in NGC 1433. Wefind also that in galaxies in which an R_1_ outer ring is prominent inthe continuum image, the H II regions follow an R^'^_2_ morphology. Inseveral cases, the observed distribution of H II regions stronglysupports the idea that the rings are linked to specific orbitalresonances with the bar. H II region luminosity functions have beenderived for all of the sample galaxies. The functions can be representedby power laws whose exponents are very similar to those found fornonringed galaxies. In a few cases, a luminous nuclear ring produces asecondary peak in the luminosity function. One galaxy shows a break inthe luminosity function similar to that observed in other galaxies byKennicutt, Edgar, & Hodge. The most unusual Hα distribution inthe sample was found in the large outer-ringed galaxy NGC 1291. Theprimary bar, lens, and secondary bar regions of this SO/a galaxy arefilled with a wispy pattern of ionized gas filaments very reminiscent ofwhat is seen in the bulge of M31.
| The Catalog of Southern Ringed Galaxies
The Catalog of Southern Ringed Galaxies (CSRG) is a comprehensivecompilation of diameters, axis ratios, relative bar position angles, andmorphologies of inner and outer rings, pseudorings, and lenses in 3692galaxies south of declination -17 deg. The purpose of the catalog is toevaluate the idea that these ring phenomena are related to orbitalresonances with a bar or oval in galaxy potentials. The catalog is basedon visual inspection of most of the 606 fields of the Science ResearchCouncil (SRC) IIIa-J southern sky survey, with the ESO-B, ESO-R, andPalomar Sky surveys used as auxiliaries when needed for overexposed coreregions. The catalog is most complete for SRC fields 1-303 (mostly southof declination -42 deg). In addition to ringed galaxies, a list of 859mostly nonringed galaxies intended for comparison with other catalogs isprovided. Other findings from the CSRG that are not based on statisticsare the identification of intrinsic bar/ring misalignment; bars whichunderfill inner rings; dimpling of R'1pseudorings; pointy, rectangular, or hexagonal inner or outer ringshapes; a peculiar polar-ring-related system; and other extreme examplesof spiral structure and ring morphology.
| 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.
| Galaxy properties in different environments. 1: The sample
This paper presents two galaxy samples, respectively in a high and in alow local density environments, that were generated from the SouthernSky Redshift Survey (SSRS) catalog using objective criteria. Apreliminary comparison of physical properties in these two samplesreveals that galaxies in high-density environments tend to be under ahigher starbursting activity, have a deficiency of the neutral hydrogencontent, present a higher fractional Seyfert population and a higherfraction of barred spirals as well. The present samples are intended tobe used in future spectroscopic observations for more detailedinvestigation.
| Galaxy properties in different environments. 2: Star formation in bulges of late-type spirals
The star formation history in the nucleus of late spiral galaxies iscompared between a sample in a high galaxy density medium (HDS) and acontrol sample (CS) of isolated galaxies. We have observed 20 HDS and 18CS galaxies from a larger list generated by the application of agroup-finding algorithm to the SSRS survey. Using equivalent widths ofabsorption lines and the continuum distribution, we determined thenuclear stellar population types, from those dominated by old populationto those containing star formation bursts of different ages andintensities. The HDS and CS stellar population type histograms aresimilar, suggesting that environmental influences, at least for thepresent sample, do not affect substantially the nuclear stellarpopulation. However, the nuclear emission lines indicate that, in theBPT diagnostic diagrams, there is an excess of HDS galaxies locatedwithin or close to the active galactic nuclei (AGN) loci. For six HDSand two CS galaxies, it was possible to determine oxygen (O/H) andnitrogen (N/H) abundances. The samples present similar O/H values, butin the CS galaxies the N/O ratio is lower at equal galaxy luminosity.
| The extended 12 micron galaxy sample
We have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns.
| Southern Sky Redshift Survey - The catalog
The catalog of radial velocities for galaxies which comprise thediameter-limited sample of the Southern Sky Redshift Survey ispresented. It consolidates the data of observations carried out at theLas Campanas Observatory, Observatorio Nacional, and South AfricanAstronomical Observatory. The criteria used for the sample selection aredescribed, as well as the observational procedures and the techniqueutilized to obtain the final radial velocities. The intercomparisonbetween radial velocity measurements from different telescopes indicatesthat the final data base is fairly homogeneous with a typical error ofabout 40 km/s. The sample is at present 90 percent complete, and themissing galaxies are predominantly objects with very low surfacebrightness for which it is very difficult to obtain optical redshifts.
| Southern Galaxy Catalogue.
Not Available
| Redshifts for 228 southern galaxies
In this paper, new redshifts are presented for 228 galaxies locatedsouth of declination -30 deg. The observations were made with aphoton-counting Reticon detector on the Observatorio Nacional (ON)60-in. telescope. The detector is identical to the one used at MountHopkins for the CfA Redshift Survey, and the redshifts were derivedusing the same data-analysis system. A preliminary comparison withpublished 21-cm redshifts indicates that the velocities have azero-point offset of about -4 km/s, with a typical uncertainty of 40km/s. The observations reported here are the initial results of theON-CfA Redshift Survey currently being undertaken in the southernhemisphere.
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