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Determination of the Thickness of Non-Edge-on Disk Galaxies
We propose a method to determine the thickness of non-edge-on diskgalaxies from their observed structure of spiral arms, based on thesolution of the truly three-dimensional Poisson's equation for alogarithmic disturbance of density and under the condition where theself-consistency of the density wave theory is no longer valid. Fromtheir measured number of arms, pitch angle and location of the innermostpoint of the spiral arms, we derive and present the thicknesses of 34spiral galaxies.
| [O II] as a Star Formation Rate Indicator
We investigate the [O II] emission line as a star formation rate (SFR)indicator using integrated spectra of 97 galaxies from the Nearby FieldGalaxies Survey (NFGS). The sample includes all Hubble types andcontains SFRs ranging from 0.01 to 100 Msolaryr-1. We compare the Kennicutt [O II] and Hα SFRcalibrations and show that there are two significant effects thatproduce disagreement between SFR([O II]) and SFR(Hα): reddeningand metallicity. Differences in the ionization state of the interstellarmedium do not contribute significantly to the observed differencebetween SFR([O II]) and SFR(Hα) for the NFGS galaxies withmetallicities log(O/H)+12>~8.5. The Kennicutt [O II]-SFR relationassumes a typical reddening for nearby galaxies; in practice, thereddening differs significantly from sample to sample. We derive a newSFR([O II]) calibration that does not contain a reddening assumption.Our new SFR([O II]) calibration also provides an optional correction formetallicity. Our SFRs derived from [O II] agree with those derived fromHα to within 0.03-0.05 dex. We show that the reddening, E(B-V),increases with intrinsic (i.e., reddening-corrected) [O II] luminosityfor the NFGS sample. We apply our SFR([O II]) calibration withmetallicity correction to two samples: high-redshift 0.8
| 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
| Vertical Scale Parameter Estimates for 48 Non-edge-on Spiral Galaxies
In the first paper of this series, we directly studied the mathematicalforms, symmetry of spiral structure, and the projection of galacticdiscs on the images, and measured the pitch angles of the spiral armsand inclination angles of the galactic discs for 60 spiral galaxies. Inthis second paper, we estimate the vertical scale parameters of 48non-edge-on spiral galaxies based on the method proposed by Peng et al.and on the results given in Paper I. As we know, for edge-on discgalaxies we can obtain the vertical scale parameter from the photometry,once a mathematical form is specified for the vertical lightdistribution. For non-edge-on galaxies, some other methods have to beused. The statistical result was that the vertical scale parameter iscomparable for edge-on and non-edge-on galaxies, although it is obtainedfrom two very different methods.
| Classifications of the Host Galaxies of Supernovae
Classifications on the DDO system are given for the host galaxies of 177supernovae (SNe) that have been discovered since 1997 during the courseof the Lick Observatory Supernova Search with the Katzman AutomaticImaging Telescope. Whereas SNe Ia occur in all galaxy types, it isfound, at a high level of statistical confidence, that SNe Ib, Ic, andII are strongly concentrated in late-type galaxies. However, attentionis drawn to a possible exception provided by SN 2001I. This SN IInoccurred in the E2 galaxy UGC 2836, which was not expected to harbor amassive young supernova progenitor.
| The Hα and Infrared Star Formation Rates for the Nearby Field Galaxy Survey
We investigate the Hα and infrared star formation rate (SFR)diagnostics for galaxies in the Nearby Field Galaxy Survey (NFGS). Forthe 81 galaxies in our sample, we derive Hα fluxes (included here)from integrated spectra. There is a strong correlation between the ratioof far-infrared to optical luminosities L(FIR)/L(Hα) and theextinction E(B-V) measured with the Balmer decrement. Before reddeningcorrection, the SFR(IR) and SFR(Hα) are related to each other by apower law: SFR(IR)=(2.7+/-0.3)SFR(Hα)1.30+/-0.06.Correction of the SFR(Hα) for extinction using the Balmerdecrement and a classical reddening curve both reduces the scatter inthe SFR(IR)-SFR(Hα) correlation and results in a much closeragreement between the two SFR indicators;SFR(IR)=(0.91+/-0.04)SFR(Hαcorr)1.07+/-0.03.SFR(IR) and SFR(Hα) agree to ~10%. This SFR relationship spans 4orders of magnitude and holds for all Hubble types with IRAS detectionsin the NFGS. A constant ratio between the SFR(IR) and SFR(Hα) forall Hubble types, including early types (S0-Sab), suggests that the IRemission in all these objects results from a young stellar population.
| 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
| A Method of Obtaining the Pitch Angle of Spiral Arms and the Inclination of Galactic Discs
We investigate the mathematical form, the symmetry of spiral structureand the projected images of galactic discs. The measured pitch angles ofspiral arms and inclination angles of galactic discs for 60 spiralgalaxies are presented. The global spiral structure is emphasized in thestudy. It is found that, except for small-scale distortions, the spiralarms of those galaxies that were classified as AC 12 in the armclassification system of Elmegreen & Elmegreen, can be representedby the logarithmic spiral form.
| Starbursts versus Truncated Star Formation in Nearby Clusters of Galaxies
We present long-slit spectroscopy, B- and R-bandpass imaging, and 21 cmobservations of a sample of early-type galaxies in nearby clusters,which are known to be either in a star-forming phase or to have had starformation that recently terminated. From the long-slit spectra, obtainedwith the Blanco 4 m telescope, we find that emission lines in thestar-forming cluster galaxies are significantly more centrallyconcentrated than in a sample of field galaxies. The broadband imagingreveals that two currently star-forming early-type galaxies in thePegasus I cluster have blue nuclei, again indicating that recent starformation has been concentrated. In contrast, the two galaxies for whichstar formation has already ended show no central color gradient. ThePegasus I galaxy with the most evident signs of ongoing star formation(NGC 7648), exhibits signatures of a tidal encounter. Neutral hydrogenobservations of that galaxy with the Arecibo radio telescope reveal thepresence of ~4×108 Msolar of H I. Areciboobservations of other current or recent star-forming early-type galaxiesin Pegasus I indicate smaller amounts of gas in one of them, and onlyupper limits in others. These observations indicate that NGC 7648 in thePegasus I cluster owes its present star formation episode to some formof tidal interaction. The same may be true for the other galaxies withcentralized star formation, but we cannot rule out the possibility thattheir outer disks have been removed via ram pressure stripping, followedby rapid quenching of star formation in the central region.
| Spectrophotometry of Nearby Field Galaxies: The Data
We have obtained integrated and nuclear spectra as well as U, B, Rsurface photometry for a representative sample of 196 nearby galaxies.These galaxies span the entire Hubble sequence in morphological type, aswell as a wide range of luminosities (MB=-14 to -22). Here wepresent the spectrophotometry for these galaxies. The selection of thesample and the U, B, R surface photometry is described in a companionpaper. Our goals for the project include measuring the current starformation rates and metallicities of these galaxies, and elucidatingtheir star formation histories, as a function of luminosity andmorphology. We thereby extend the work of Kennicutt to lower luminositysystems. We anticipate that our study will be useful as a benchmark forstudies of galaxies at high redshift. We describe the observing, datareduction, and calibration techniques and demonstrate that ourspectrophotometry agrees well with that of Kennicutt. The spectra spanthe range 3550-7250 Å at a resolution (FWHM) of ~6 Å andhave an overall relative spectrophotometric accuracy of ~+/-6%. Wepresent a spectrophotometric atlas of integrated and nuclear rest-framespectra as well as tables of equivalent widths and synthetic colors. Theatlas and tables of measurements will be made available electronically.We study the correlations of galaxy properties determined from thespectra and images. Our findings include: (1) galaxies of a givenmorphological class display a wide range of continuum shapes andemission-line strengths if a broad range of luminosities are considered,(2) emission-line strengths tend to increase and continua tend to getbluer as the luminosity decreases, and (3) the scatter on the generalcorrelation between nuclear and integrated Hα emission-linestrengths is large.
| Surface Photometry of Nearby Field Galaxies: The Data
We have obtained integrated spectra and multifilter photometry for arepresentative sample of ~200 nearby galaxies. These galaxies span theentire Hubble sequence in morphological type, as well as a wide range ofluminosities (MB=-14 to -22) and colors (B-R=0.4-1.8). Herewe describe the sample selection criteria and the U, B, R surfacephotometry for these galaxies. The spectrophotometric results will bepresented in a companion paper. Our goals for the project includemeasuring the current star formation rates and metallicity of thesegalaxies, and elucidating their star formation histories, as a functionof luminosity and morphology. We thereby extend the work of Kennicutt tolower luminosity systems. We anticipate that our study will be useful asa benchmark for studies of galaxies at high redshift. We discuss theobserving, data reduction, and calibration techniques and show that ourphotometry agrees well with previous work in those cases in whichearlier data are available. We present an atlas of images, radialsurface brightness profiles, and color profiles as well as tables ofderived parameters. The atlas and tables of measurements will be madeavailable electronically. We study the correlations of galaxy propertiesdetermined from the galaxy images. Our findings include the following:(1) colors determined within the effective radius correlate better withmorphological type than with MB and (2) 50% of thelow-luminosity galaxies are bluest in their centers.
| 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.
| Supernova 1999A in NGC 5874
IAUC 7086 available at Central Bureau for Astronomical Telegrams.
| Supernova 1999A in NGC 5874
IAUC 7083 available at Central Bureau for Astronomical Telegrams.
| 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.
| The I-Band Tully-Fisher Relation for SC Galaxies: 21 Centimeter H I Line Data
A compilation of 21 cm line spectral parameters specifically designedfor application of the Tully-Fisher (TF) distance method is presentedfor 1201 spiral galaxies, primarily field Sc galaxies, for which opticalI-band photometric imaging is also available. New H I line spectra havebeen obtained for 881 galaxies. For an additional 320 galaxies, spectraavailable in a digital archive have been reexamined to allow applicationof a single algorithm for the derivation of the TF velocity widthparameter. A velocity width algorithm is used that provides a robustmeasurement of rotational velocity and permits an estimate of the erroron that width taking into account the effects of instrumental broadeningand signal-to-noise. The digital data are used to establish regressionrelations between measurements of velocity widths using other commonprescriptions so that comparable widths can be derived throughconversion of values published in the literature. The uniform H I linewidths presented here provide the rotational velocity measurement to beused in deriving peculiar velocities via the TF method.
| The I-Band Tully-Fisher Relation for SC Galaxies: Optical Imaging Data
Properties derived from the analysis of photometric I-band imagingobservations are presented for 1727 inclined spiral galaxies, mostly oftypes Sbc and Sc. The reduction, parameter extraction, and errorestimation procedures are discussed in detail. The asymptotic behaviorof the magnitude curve of growth and the radial variation in ellipticityand position angle are used in combination with the linearity of thesurface brightness falloff to fit the disk portion of the profile. TotalI-band magnitudes are calculated by extrapolating the detected surfacebrightness profile to a radius of eight disk scale lengths. Errors inthe magnitudes, typically ~0.04 mag, are dominated by uncertainties inthe sky subtraction and disk-fitting procedures. Comparison is made withthe similar imaging database of Mathewson, Ford, & Buchhorn, both aspresented originally by those authors and after reanalyzing theirdigital reduction files using identical disk-fitting procedures. Directcomparison is made of profile details for 292 galaxies observed incommon. Although some differences occur, good agreement is found,proving that the two data sets can be used in combination with onlyminor accommodation of those differences. The compilation of opticalproperties presented here is optimized for use in applications of theTully-Fisher relation as a secondary distance indicator in studies ofthe local peculiar velocity field.
| Groups of galaxies. III. Some empirical characteristics.
Not Available
| 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.
| 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.
| The UV properties of normal galaxies. III. Standard luminosity profiles and total magnitudes.
In the previous papers of this series we collected and reduced to thesame system all the available photometric data obtained in theultraviolet (UV) range for normal (i.e. non active) galaxies. Here weuse these data to derive standard UV luminosity profiles for threemorphological bins (E/S0; Sa/Sb; Sc/Sd) and extrapolated totalmagnitudes for almost 400 galaxies. We find that: 1) the UV growthcurves are well matched by the B-band revised standard luminosityprofiles, once a proper shift in the effective radius is applied, and 2)the UV light in early-type galaxies is more centrally concentrated thanthe visible light.
| The UV properties of normal galaxies. II. The ``non-IUE'' data.
In the last decade several satellite and balloon borne experiments havecollected a large number of ultraviolet fluxes of normal galaxiesmeasured through apertures of various sizes and shapes. We havehomogenized this data set by deriving scale corrections with respect toIUE. In a forthcoming paper these data will be used to derive standardluminosity profiles and total magnitudes.
| A revised catalog of CfA1 galaxy groups in the Virgo/Great Attractor flow field
A new identification of groups and clusters in the CfA1 Catalog ofHuchra et al. is presented, using a percolation algorithm to identifydensity enhancements. It is shown that in the resulting catalog,contamination by interlopers is significantly reduced. The Schechterluminosity function is redetermined, including the Malmquist bias.
| General study of group membership. II - Determination of nearby groups
We present a whole sky catalog of nearby groups of galaxies taken fromthe Lyon-Meudon Extragalactic Database. From the 78,000 objects in thedatabase, we extracted a sample of 6392 galaxies, complete up to thelimiting apparent magnitude B0 = 14.0. Moreover, in order to considersolely the galaxies of the local universe, all the selected galaxieshave a known recession velocity smaller than 5500 km/s. Two methods wereused in group construction: a Huchra-Geller (1982) derived percolationmethod and a Tully (1980) derived hierarchical method. Each method gaveus one catalog. These were then compared and synthesized to obtain asingle catalog containing the most reliable groups. There are 485 groupsof a least three members in the final catalog.
| Groups of galaxies within 80 Mpc. II - The catalogue of groups and group members
This paper gives a catalog of the groups and associations obtained bymeans of a revised hierarchical algorithm applied to a sample of 4143galaxies with diameters larger than 100 arcsec and redshifts smallerthan 6000 km/s. The 264 groups of galaxies obtained in this way (andwhich contain at least three sample galaxies) are listed, with the looseassociations surrounding them and the individual members of eachaggregate as well; moreover, the location of every entity among 13regions corresponding roughly to superclusters is specified. Finally,1729 galaxies belong to the groups, and 466 to the associations, i.e.,the total fraction of galaxies within the various aggregates amounts to53 percent.
| 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.
| A deep redshift survey of IRAS galaxies towards the Bootes void
Redshifts were measured for a complete sample of galaxies detected bythe IRAS within 11.5 deg of the center of the void in Bootes discoveredby Kirshner et al (1981). There are 12 IRAS galaxies within the void asdefined by the above authors, seven of which were discovered in thissurvey. One of these has a companion at the same redshift. The resultingdensity of IRAS galaxies in the void is measured to be between 1/6 and1/3 of the average density; the uncertainty is dominated by Poissonstatistics. Good agreement is found between the selection function andnumber density derived from the present sample and those derived fromthe all-sky sample of Strauss (1989). The optical spectra of the newlyfound galaxies in the void are typical of IRAS galaxies in the field.
| Cosmology from a galaxy group catalog. I - Binaries
A new, completely objective group-finding algorithm is described andapplied to the CfA redshift catalog. The binary galaxies are isolatedfor analysis. The assumptions underlying the analysis are (1) that lighttraces mass, (2) that our binary galaxy subsets are representative lighttracers, and (3) that the binary orbits are circular. The primary resultof the work is that the resulting bias-free binary catalogs are afunction of the assumed cosmological model. For virtually any inputvalue of Omega(0) in the range 0.01-5.00, there is a reasonablyconsistent interpretation of the CfA survey such that the specifiedvalue of Omega(0) can be derived from the binary sample obtained underthat interpretation. A secondary result is that the higher the inputvalue of Omega(0), the broader the intrinsic distribution in M/L, andhence the less valid the assumption that light traces mass.
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