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The evolution of actively star-forming galaxies in the mid-infrared
In this paper we analyze the evolution of actively star-forming galaxiesin the mid-infrared (MIR). This spectral region, characterized bycontinuum emission by hot dust and by the presence of strong emissionfeatures generally ascribed to polycyclic aromatic hydrocarbon (PAH)molecules, is the most strongly affected by the heating processesassociated with star formation and/or active galactic nuclei (AGNs).Following the detailed observational characterization of galaxies in theMIR by the Infrared Space Observatory (ISO), we have updated themodelling of this spectral region in our spectrophotometric modelGRASIL. In the diffuse component we have updated the treatment of PAHsaccording to the model by Li & Draine. As for the dense phase of theinterstellar medium associated with the star-forming regions, themolecular clouds, we strongly decrease the abundance of PAHs as comparedto that in the cirrus, based on the observational evidence of the lackor weakness of PAH bands close to the newly formed stars, possibly dueto the destruction of the molecules in strong ultraviolet fields. Therobustness of the model is checked by fitting near-infrared to radiobroad-band spectra and the corresponding detailed MIR spectra of a largesample of galaxies, at once. With this model, we have analyzed thelarger sample of actively star-forming galaxies by Dale et al. We showthat the observed trends of galaxies in the ISO-IRAS-radio colour-colourplots can be interpreted in terms of the different evolutionary phasesof star formation activity, and the consequent different dominance inthe spectral energy distribution of the diffuse or dense phase of theISM. We find that the observed colours indicate a surprising homogeneityof the starburst phenomenon, allowing only a limited variation of themost important physical parameters, such as the optical depth of themolecular clouds, the time-scale of the escape of young stars from theirfor mation sites, and the gas consumption time-scale. In this paper wedo not attempt to reproduce the far-infrared coolest region in thecolour-colour plots, as we concentrate on models meant to reproduceactive star-forming galaxies, but we discuss possible requirements of amore complex modelling for the coldest objects.
| Simulating the Spitzer Mid-Infrared Color-Color Diagrams
We use a simple parameterization of the mid-IR spectra of a wide rangeof galaxy types in order to predict their distribution in the InfraredArray Camera (IRAC) 3.6, 4.5, 5.8, and 8.0 μm and MultibandPhotometer for Spitzer 24 μm color-color diagrams. We distinguishthree basic spectral types by the energetically dominant component inthe 3-12 μm regime: stellar-dominated, polycyclic aromatichydrocarbon (PAH)-dominated, and continuum-dominated. We use a Markovchain Monte Carlo approach to arrive at a more systematic and robustrepresentation of the mid-IR spectra of galaxies than do moretraditional approaches. We find that IRAC color-color plots are wellsuited to distinguishing the above spectral types, while the addition of24 μm data allows us to suggest practical three-color cuts thatpreferentially select higher redshift sources of a specific type. Wecompare our simulations with the color-color plot obtained by theSpitzer First Look Survey and find reasonable agreement. Lastly, wediscuss other applications as well as future directions for this work.
| Classification of Spectra from the Infrared Space Observatory PHT-S Database
We have classified over 1500 infrared spectra obtained with the PHT-Sspectrometer aboard the Infrared Space Observatory according to thesystem developed for the Short Wavelength Spectrometer (SWS) spectra byKraemer et al. The majority of these spectra contribute to subclassesthat are either underrepresented in the SWS spectral database or containsources that are too faint, such as M dwarfs, to have been observed byeither the SWS or the Infrared Astronomical Satellite Low ResolutionSpectrometer. There is strong overall agreement about the chemistry ofobjects observed with both instruments. Discrepancies can usually betraced to the different wavelength ranges and sensitivities of theinstruments. Finally, a large subset of the observations (~=250 spectra)exhibit a featureless, red continuum that is consistent with emissionfrom zodiacal dust and suggest directions for further analysis of thisserendipitous measurement of the zodiacal background.Based on observations with the Infrared Space Observatory (ISO), aEuropean Space Agency (ESA) project with instruments funded by ESAMember States (especially the Principle Investigator countries: France,Germany, Netherlands, and United Kingdom) and with the participation ofthe Institute of Space and Astronautical Science (ISAS) and the NationalAeronautics and Space Administration (NASA).
| Near-Infrared Integral Field Spectroscopy of Star-forming Galaxies
The Palomar Integral Field Spectrograph was used to probe a variety ofenvironments in nine nearby galaxies that span a range of morphologicaltypes, luminosities, metallicities, and infrared-to-blue ratios. For thefirst time, near-infrared spectroscopy was obtained for nuclear orbright H II regions in star-forming galaxies over two spatial dimensions(5.7"×10.0") in the [Fe II] (1.257 μm), [Fe II] (1.644 μm),Paβ (1.282 μm), H2 (2.122 μm), and Brγ(2.166 μm) transition lines. These data yield constraints on variouscharacteristics of the star-forming episodes in these regions, includingtheir strength, maturity, spatial variability, and extinction. The H IIregions stand out from the nuclei. Unlike observations of nuclearregions, H II region near-infrared observations do not show a spatialcoincidence of the line and continuum emission; the continuum and linemaps of H II regions usually show distinct and sometimes spatiallyseparated morphologies. Gauging from Paβ and Brγ equivalentwidths and luminosities, the H II regions have younger episodes of starformation than the nuclei and more intense radiation fields.Near-infrared line ratio diagnostics suggest that H II regions have``purer'' starbursting properties. The correlation between ionizingphoton density and mid-infrared color is consistent with the starformation activity level being higher for H II regions than for nuclei.And though the interpretation is complicated, on a purely empiricalbasis the H II regions show lower Fe1+ abundances than nucleiby an order of magnitude.
| 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
| Infrared Emission of Normal Galaxies from 2.5 to 12 Micron: Infrared Space Observatory Spectra, Near-Infrared Continuum, and Mid-Infrared Emission Features
We present ISOPHOT spectra of the regions 2.5-4.9 μm and 5.8-11.6μm for a sample of 45 disk galaxies from the US Infrared SpaceObservatory Key Project on Normal Galaxies. The galaxies were selectedto span the range in global properties of normal, star-forming diskgalaxies in the local universe. The spectra can be decomposed into threespectral components: (1) continuum emission from stellar photospheres,which dominates the near-infrared (NIR; 2.5-4.9 μm) spectral region;(2) a weak NIR excess continuum, which has a color temperature of~103 K, carries a luminosity of a few percent of the totalfar-infrared (FIR) dust luminosity LFIR and most likelyarises from the interstellar medium (ISM); and (3) the well-known broademission features at 6.2, 7.7, 8.6, and 11.3 μm, which are generallyattributed to aromatic carbon particles. These aromatic features inemission (AFEs) dominate the mid-infrared (MIR; 5.8-11.6 μm) part ofthe spectrum and resemble the so-called type A spectra observed in manynonstellar sources and the diffuse ISM in our own Galaxy. The fewnotable exceptions include NGC 4418, where a dust continuum replaces theAFEs in MIR, and NGC 1569, where the AFEs are weak and the strongestemission feature is [S IV] 10.51 μm. The relative strengths of theAFEs vary by 15%-25% among the galaxies. However, little correlation isseen between these variations and either IRAS 60 μm/100 μm fluxdensity ratio R(60/100) or the FIR/blue luminosity ratioLFIR/LB, two widely used indicators of the currentstar formation activity, suggesting that the observed variations are nota consequence of the radiation field differences among the galaxies. Wedemonstrate that the NIR excess continuum and AFE emission arecorrelated, suggesting that they are produced by similar mechanisms andsimilar (or the same) material. On the other hand, as the current starformation activity increases, the overall strengths of the AFEs and theNIR excess continuum drop significantly with respect to that of the FIRemission from large dust grains. In particular, the summed luminosity ofthe AFEs falls from ~0.2 LFIR for the most ``IR-quiescent''galaxies to ~0.1 LFIR for the most ``IR-active'' galaxies.This is likely a consequence of the preferential destruction in intenseradiation fields of the small carriers responsible for the NIR/AFEemission.Based on observations with ISO, an ESA project with instruments fundedby ESA member states (especially the PI countries, France, Germany, theNetherlands, and the United Kingdom) and with the participation of ISASand NASA.
| 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.
| Local velocity field from sosie galaxies. I. The Peebles' model
Pratton et al. (1997) showed that the velocity field around clusterscould generate an apparent distortion that appears as tangentialstructures or radial filaments. In the present paper we determine theparameters of the Peebles' model (1976) describing infall of galaxiesonto clusters with the aim of testing quantitatively the amplitude ofthis distortion. The distances are determined from the concept of sosiegalaxies (Paturel 1984) using 21 calibrators for which the distanceswere recently calculated from two independent Cepheid calibrations. Weuse both B and I-band magnitudes. The Spaenhauer diagram method is usedto correct for the Malmquist bias. We give the equations for theconstruction of this diagram. We analyze the apparent Hubble constant indifferent regions around Virgo and obtain simultaneously the Local Groupinfall and the unperturbed Hubble constant. We found:[VLG-infall = 208 ± 9 km s-1] [\log H =1.82 ± 0.04 (H ≈ 66 ± 6 km s-1Mpc-1).] The front side and backside infalls can be seenaround Virgo and Fornax. In the direction of Virgo the comparison ismade with the Peebles' model. We obtain: [vinfall} =CVirgo/r0.9 ± 0.2] withCVirgo=2800 for Virgo and CFornax=1350 for Fornax,with the adopted units (km s-1 and Mpc). We obtain thefollowing mean distance moduli: [μVirgo=31.3 ± 0.2(r=18 Mpc )] [μFornax=31.7 ± 0.3 (r=22 Mpc). ] Allthese quantities form an accurate and coherent system. Full Table 2 isonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/57
| Far-Infrared Spectroscopy of Normal Galaxies: Physical Conditions in the Interstellar Medium
The most important cooling lines of the neutral interstellar medium(ISM) lie in the far-infrared (FIR). We present measurements by theInfrared Space Observatory Long Wavelength Spectrometer of seven linesfrom neutral and ionized ISM of 60 normal, star-forming galaxies. Thegalaxy sample spans a range in properties such as morphology, FIR colors(indicating dust temperature), and FIR/blue ratios (indicating starformation activity and optical depth). In two-thirds of the galaxies inthis sample, the [C II] line flux is proportional to FIR dust continuum.The other one-third show a smooth decline inL[CII]/LFIR with increasing Fν(60μm)/Fν(100 μm) and LFIR/LB,spanning a range of a factor of more than 50. Two galaxies at the warmand active extreme of the range haveL[CII]/LFIR<2×10-4 (3 σupper limit). This is due to increased positive grain charge in thewarmer and more active galaxies, which leads to less efficient heatingby photoelectrons from dust grains. The ratio of the two principalphotodissociation region (PDR) cooling linesL[OI]/L[CII] shows a tight correlation withFν(60 μm)/Fν(100 μm), indicating thatboth gas and dust temperatures increase together. We derive atheoretical scaling between [N II] (122 μm) and [C II] from ionizedgas and use it to separate [C II] emission from neutral PDRs and ionizedgas. Comparison of PDR models of Kaufman et al. with observed ratios of(1) L[OI]/L[CII] and(L[CII]+L[OI])/LFIR and (2)L[OI]/LFIR and Fν(60μm)/Fν(100 μm) yields far-UV flux G0 andgas density n. The G0 and n values estimated from the twomethods agree to better than a factor of 2 and 1.5, respectively, inmore than half the sources. The derived G0 and n correlatewith each other, and G0 increases with n asG0~nα, where α~1.4 . We interpret thiscorrelation as arising from Strömgren sphere scalings if much ofthe line and continuum luminosity arises near star-forming regions. Thehigh values of PDR surface temperature (270-900 K) and pressure(6×104-1.5×107 K cm-3)derived also support the view that a significant part of grain and gasheating in the galaxies occurs very close to star-forming regions. Thedifferences in G0 and n from galaxy to galaxy may be due todifferences in the physical properties of the star-forming clouds.Galaxies with higher G0 and n have larger and/or denserstar-forming clouds.
| The relationship between star formation rates and mid-infrared emission in galactic disks
The Hα and mid-infrared mean disk surface brightnesses arecompared in a sample of nearby spirals observed by ISOCAM. This showsthat, in spiral disks, dust emission at 7 and 15 mu m provides areasonable star formation tracer. The fact that the 15 to 7 mu m fluxratio is nearly constant in various global exciting conditions indicatesa common origin, namely the aromatic infrared band carriers, and impliesthat at these wavelengths, dust emission from the disks of normalgalaxies is dominated by photodissociation regions and not by H Iiregions themselves. We use this newly-found correlation between themid-infrared and the Hα line to investigate the nature of the linkbetween the far-infrared (60 and 100 mu m) and Hα . Although theseparation of the central regions from the disk is impossible to achievein the far-infrared, we show that a circumnuclear contribution to thedust emission, having no equivalent counterpart in Hα , is mostlikely responsible for the well-known non-linearity between far-infraredand Hα fluxes in spiral galaxies. We derive a calibration of 7 and15 mu m fluxes in terms of star formation rates from a primarycalibration of Hα in the literature, and also outline theapplicability limits of the proposed conversion, which should not beblindly extrapolated to objects whose nature is unknown. Based onobservations with ISO, an ESA project with instruments funded by ESAMember States (especially the PI countries: France, Germany, TheNetherlands and the UK) and with the participation of ISAS and NASA.
| The impact of bars on the mid-infrared dust emission of spiral galaxies: global and circumnuclear properties
We study the mid-infrared properties of a sample of 69 nearby spiralgalaxies, selected to avoid Seyfert activity contributing a significantfraction of the central energetics, or strong tidal interaction, and tohave normal infrared luminosities. These observations were obtained withISOCAM, which provides an angular resolution of the order of 10arcsec(half-power diameter of the point spread function) and low-resolutionspectro-imaging information. Between 5 and 18 mu m, we mainly observetwo dust phases, aromatic infrared bands and very small grains, both outof thermal equilibrium. On this sample, we show that the globalF15/F_7 colors of galaxies are very uniform, the onlyincrease being found in early-type strongly barred galaxies, consistentwith previous IRAS studies. The F15/F_7 excesses areunambiguously due to galactic central regions where bar-inducedstarbursts occur. However, the existence of strongly barred early-typegalaxies with normal circumnuclear colors indicates that therelationship between a distortion of the gravitational potential and acentral starburst is not straightforward. As the physical processes atwork in central regions are in principle identical in barred andunbarred galaxies, and since this is where the mid-infrared activity ismainly located, we investigate the mid-infrared circumnuclear propertiesof all the galaxies in our sample. We show how surface brightnesses andcolors are related to both the available molecular gas content and themean age of stellar populations contributing to dust heating. Therefore,the star formation history in galactic central regions can beconstrained by their position in a color-surface brightness mid-infrareddiagram. Based on observations with ISO, an ESA project with instrumentsfunded by ESA Member States (especially the PI countries: France,Germany, the Netherlands and the UK) and with the participation of ISASand NASA.
| The mass distribution in the innermost regions of spiral galaxies
We use high-spatial resolution ( ~ 100 pc) rotation curves of 83 spiralgalaxies to investigate the mass distribution of their innermost kpc. Weshow that in this region the luminous matter completely accounts for thegravitational potential and no dark component is required. The derivedI-band disk mass-to-light ratios Y_I agree well with those obtained frompopulation synthesis models and correlate with color in a similar way.We find strict upper limits of ~ 10^7 M_Sun for the masses of compactbodies at the center of spirals ruling out that these systems host theremnants of the quasar activity.
| ISO Mid-Infrared Observations of Normal Star-Forming Galaxies: The Key Project Sample
We present mid-infrared maps and preliminary analysis for 61 galaxiesobserved with the ISOCAM instrument aboard the Infrared SpaceObservatory. Many of the general features of galaxies observed atoptical wavelengths-spiral arms, disks, rings, and bright knots ofemission-are also seen in the mid-infrared, except the prominent opticalbulges are absent at 6.75 and 15 μm. In addition, the maps are quitesimilar at 6.75 and 15 μm, except for a few cases where a centralstarburst leads to lower Iν(6.75μm)/Iν(15 μm) ratios in the inner region. We alsopresent infrared flux densities and mid-infrared sizes for thesegalaxies. The mid-infrared color Iν(6.75μm)/Iν(15 μm) shows a distinct trend with thefar-infrared color Iν(60 μm)/Iν(100μm). The quiescent galaxies in our sample [Iν(60μm)/Iν(100 μm)<~0.6] show Iν(6.75μm)/Iν(15 μm) near unity, whereas this ratio dropssignificantly for galaxies with higher global heating intensity levels.Azimuthally averaged surface brightness profiles indicate the extent towhich the mid-infrared flux is centrally concentrated, and provideinformation on the radial dependence of mid-infrared colors. Thegalaxies are mostly well resolved in these maps: almost half of themhave <10% of their flux in the central resolution element. Acomparison of optical and mid-infrared isophotal profiles indicates thatthe flux at 4400 Å near the optical outskirts of the galaxies isapproximately 8 (7) times that at 6.75 μm (15 μm), comparable toobservations of the diffuse quiescent regions of the Milky Way. Thispaper is based on observations with the Infrared Space Observatory(ISO). ISO is an ESA project with instruments funded by ESA memberstates (especially the PI countries: France, Germany, The Netherlands,and the United Kingdom) and with the participation of ISAS and NASA.
| 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
| Bulge-Disk Decomposition of 659 Spiral and Lenticular Galaxy Brightness Profiles
We present one of the largest homogeneous sets of spiral and lenticulargalaxy brightness profile decompositions completed to date. The 659galaxies in our sample have been fitted with a de Vaucouleurs law forthe bulge component and an inner-truncated exponential for the diskcomponent. Of the 659 galaxies in the sample, 620 were successfullyfitted with the chosen fitting functions. The fits are generally welldefined, with more than 90% having rms deviations from the observedprofile of less than 0.35 mag. We find no correlations of fittingquality, as measured by these rms residuals, with either morphologicaltype or inclination. Similarly, the estimated errors of the fittedcoefficients show no significant trends with type or inclination. Thesedecompositions form a useful basis for the study of the lightdistributions of spiral and lenticular galaxies. The object base issufficiently large that well-defined samples of galaxies can be selectedfrom it.
| 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.
| 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.
| A catalogue of spatially resolved kinematics of galaxies: Bibliography
We present a catalogue of galaxies for which spatially resolved data ontheir internal kinematics have been published; there is no a priorirestriction regarding their morphological type. The catalogue lists thereferences to the articles where the data are published, as well as acoded description of these data: observed emission or absorption lines,velocity or velocity dispersion, radial profile or 2D field, positionangle. Tables 1, 2, and 3 are proposed in electronic form only, and areavailable from the CDS, via anonymous ftp to cdsarc.u-strasbg.fr (to130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
| Optical Rotation Curves and Linewidths for Tully-Fisher Applications
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2402C&db_key=AST
| Parameters of 2447 Southern Spiral Galaxies for Use in the Tully-Fisher Relation
I-band luminosities, rotational velocities, and redshifts of 1092 spiralgalaxies have been measured by CCD photometry and Hα spectroscopyusing the 1 m and 2.3 m telescopes at Siding Spring Observatory,respectively. The results are tabulated. Luminosity profiles andHα rotation curves are given for the galaxies. When these resultsare combined with similar data for 1355 spiral galaxies publishedpreviously (Mathewson, Ford, & Buchhorn, hereafter Paper I), itprovides a large, uniform, and unique data set with which to measure,via the Tully-Fisher relation, the peculiar velocities of galaxies inthe local universe to a distance of 11,000 km s^-1^ (Mathewson &Ford). Taking advantage of the opportunity for publishing this data inmachine-readable form, in the CD-ROM, we have also included similar datafor the 1355 galaxies in Paper I.
| Rotation Curves of 967 Spiral Galaxies
We present the rotation curves of 967 southern spiral galaxies, obtainedby deprojecting and folding the raw Hα data originally publishedby Mathewson, Ford, & Buchhorn (1992). For 900 objects, we alsopresent, in figures and tables, the rotation curves smoothed on scalescorresponding to 5%-20% of the optical size; of these, 80 meet objectiveexcellence criteria and are suitable for individual detailed massmodeling, while 820, individually less compelling mainly because of themoderate statistics and/or limited extension, are suitable forstatistical studies. The remaining 67 curves suffer from severeasymmetries, small statistics, and large internal scatter that maylargely limit their use in galaxy structure studies. The deprojectedfolded curves, the smoothed curves, and various related quantities areavailable via anonymous ftp at galileo.sissa.it in the directory/users/ftp/pub/psrot.
| 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.
| CCD calibration of the magnitude scale for the SSRS2 sample: The equatorial region
In this paper we continue our investigation on the isophotal nature,accuracy, and uniformity of the magnitude system adopted in the SouthernSky Redshift Survey extension (SSRS2). Extending our earlier work, weexamine galaxies in the equatorial region, primarily in the declinationrange delta greater than or equal to -17.5 deg and less than or equal to0 deg, over a large range of right ascension, covering the southern andnorthern Galactic caps. For this purpose, we have obtained CCD isophotalmagnitudes in the B and R bands for 265 galaxies of differentmorphological types. Using the larger sample we confirm our earlierclaim that the mSSRS2 magnitudes are very nearly themagnitude measured within the isophote muB = 26 mag/sqarcsec, with a dispersion of about 0.30 mag. The relative zero-pointoffset between our mSSRS2 magnitudes and the CCD photometryis -0.02 mag from all data we have obtained. However, we detect avariation of the zero-point across different regions of the sky of +/-0.10 mag for regions at large angular separations. We also estimate thatthe zero-point offset between the mSSRS2 and Zwicky systemsis relatively small (approximately 0.10 mag), which should allow us tocombine the data from the SSRS2 and the CfA2 Redshift Survey.
| 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.
| Effect of Malmquist bias on correlation studies with IRAS data base
The relationships between galaxy properties in the sample of Trinchieriet al. (1989) are reexamined with corrections for Malmquist bias. Thelinear correlations are tested and linear regressions are fit forlog-log plots of L(FIR), L(H-alpha), and L(B) as well as ratios of thesequantities. The linear correlations for Malmquist bias are correctedusing the method of Verter (1988), in which each galaxy observation isweighted by the inverse of its sampling volume. The linear regressionsare corrected for Malmquist bias by a new method invented here in whicheach galaxy observation is weighted by its sampling volume. The resultsof correlation and regressions among the sample are significantlychanged in the anticipated sense that the corrected correlationconfidences are lower and the corrected slopes of the linear regressionsare lower. The elimination of Malmquist bias eliminates the nonlinearrise in luminosity that has caused some authors to hypothesizeadditional components of FIR emission.
| The morphological catalogue of galaxies equatorial survey
We present 865 redshifts of galaxies located in the equatorial stripdelta between -17.5 deg and -2.5 deg in the right ascension rangebetween 20 h and 5 h. Redshifts have been obtained for the completesample of all 833 galaxies in the Morphological Catalog of Galaxies withmagnitudes brighter than m = 14.5 (corresponding approximately tom(Zwicky) = 15.0). This sample also includes three galaxies from othersources with more reliable magnitudes, satisfying this limit, and 29fainter galaxies, usually companions of the galaxies in the magnitudelimited sample. Our maps of a very large volume of nearby spacedemonstrate a variety of coherent large scale structures which includelarge voids, 20-50/h Mpc in diameter and large walls at least 70/h Mpcacross.
| A southern sky survey of the peculiar velocities of 1355 spiral galaxies
The paper presents data from photometric and spectroscopic observationsof 1355 southern spiral galaxies and uses them to determine theirdistances and peculiar velocities via the Tully-Fisher (TF) relation.I-band CCD surface photometry was carried out using the 1-m and 3.9-mtelescopes at Siding Spring Observatory. H-alpha rotation curves for 965galaxies and 551 H I profiles are presented. The physical parameters,photometric and velocity data, distances, and peculiar velocities of thegalaxies are presented in tabular form. The mean distance, systemicvelocity, and average peculiar velocity of 24 clusters in the sample aregiven. TF diagrams are presented for each cluster.
| The Tully-Fisher relation in different environments
The Tully-Fisher relation (TFR) in different environments wasinvestigated in 13 galaxy samples spanning a large range in galaxydensities, using two statistical tests to compare the TFR of differentsamples. Results of the analysis of TFR parameters in severalenvironments showed that, when samples of similar data-accuracy andmagnitude-range were compared, there was no significant differencebetween the galaxy samples. It is suggested that a comparison of sampleswith very different data accuracy or those biased by incompletenesseffects may lead to misleading results.
| The Hubble relation - Differences between galaxy types SB and SC
It is shown that the Sb galaxies have apparent magnitudes which varyalmost exactly as if their redshifts were a measure of the distance atwhich they are observed, while the Sc do not exhibit a linear Hubblerelation. An attempt is made to determine whether the Sc discordancefrom the Hubble law is caused by Malmquist bias operating in thisfainter luminosity class of galaxies or there are inherent fundamentalpeculiarities. To this purpose the search is undertaken for other kindsof galaxies physically associated which these deviating Sc's. It isshown that luminosity criterion (Tully-Fisher) gives much smallerdistances for these galaxies than their redshifts do. The interaction ofspecific high redshift ScI's with nearby galaxies is presented as anindependent proof that ScI's are generally small, low luminositygalaxies.
| Revised supernova rates in Shapley-Ames galaxies
Observations of 855 Shapley Ames galaxies made from November 1, 1980 toOctober 31, 1988, together with improved supernova luminosities, havebeen used to derive the frequency of supernovae of different types, andthe results are presented in tables. From a uniform database of 24supernovae discovered, the following SN rates are found, expressed in SNper century per 10 to the 10th L(B)(solar): SN Ia, 0.3; SN Ib, 0.3; andSN II, 1.0. The present data confirm the relatively high frequency of SNII in late-type galaxies that has been found by many previousinvestigators.
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