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Active and Star-forming Galaxies and Their Supernovae
To investigate the extent to which nuclear starbursts or other nuclearactivity may be connected with enhanced star formation activity in thehost galaxy, we perform a statistical investigation of supernovae (SNe)discovered in host galaxies from four samples: the Markarian galaxiessample, the Second Byurakan Survey (SBS) sample, the north Galactic pole(NGP) sample of active or star-forming galaxies, and the NGP sample ofnormal galaxies. Forty-seven SNe in 41 Mrk galaxies, 10 SNe in six SBSgalaxies, 29 SNe in 26 NGP active or star-forming galaxies, and 29 SNein 26 NGP normal galaxies have been studied. We find that the rate ofSNe, particularly core-collapse (Types Ib/c and II) SNe, is higher inactive or star-forming galaxies in comparison with normal galaxies.Active or star-forming host galaxies of SNe are generally of latermorphological type and have lower luminosity and smaller linear sizethan normal host galaxies of SNe. The radial distribution of SNe inactive and star-forming galaxies shows a higher concentration toward thecenter of the active host galaxy than is the case for normal hostgalaxies, and this effect is more pronounced for core-collapse SNe.Ib/c-type SNe have been discovered only in active and star-forminggalaxies of our samples. About 78% of these SNe are associated with H IIregions or are located very close to the nuclear regions of these activegalaxies, which are in turn hosting AGNs or starburst nuclei. Besidesthese new results, our study also supports the conclusions of severalother earlier papers. We find that Type Ia SNe occur in all galaxytypes, whereas core-collapse SNe of Types Ib/c and II are found only inspiral and irregular galaxies. The radial distribution of Type Ib SNe intheir host galaxies is more centrally concentrated than that of Type IIand Ia SNe. The radial distances of Types Ib/c and II SNe, from thenuclei of their host galaxies, is larger for barred spiral hosts.Core-collapse SNe are concentrated in spiral arms and are often close toor in the H II regions, whereas Type Ia SNe show only a looseassociation with spiral arms and no clear association with H II regions.
| Measuring shapes of galaxy images - II. Morphology of 2MASS galaxies
We study a sample of 112 galaxies of various Hubble types imaged in theTwo Micron All Sky Survey (2MASS) in the near-infrared (NIR; 1-2 μm)J, H and Ks bands. The sample contains (optically classified)32 ellipticals, 16 lenticulars and 64 spirals acquired from the 2MASSExtended Source Catalogue (XSC).We use a set of non-parametric shape measures constructed from theMinkowski functionals (MFs) for galaxy shape analysis. We useellipticity (ɛ) and orientation angle (Φ) as shapediagnostics. With these parameters as functions of area within theisophotal contour, we note that the NIR elliptical galaxies withɛ > 0.2 show a trend of being centrally spherical andincreasingly flattened towards the edge, a trend similar to images inoptical wavelengths. The highly flattened elliptical galaxies showstrong change in ellipticity between the centre and the edge. Thelenticular galaxies show morphological properties resembling eitherellipticals or disc galaxies. Our analysis shows that almost half of thespiral galaxies appear to have bar-like features while the rest arelikely to be non-barred. Our results also indicate that almost one-thirdof spiral galaxies have optically hidden bars.The isophotal twist noted in the orientations of elliptical galaxiesdecreases with the flattening of these galaxies, indicating that twistand flattening are also anticorrelated in the NIR, as found in opticalwavelengths. The orientations of NIR lenticular and spiral galaxies showa wide range of twists.
| Kinematics of AWM and MKW Poor Clusters
We have measured 1365 redshifts to a limiting magnitude of R~15.5 in 15AWM/MKW clusters and have collected another 203 from the literature inMKW 4s, MKW 2, and MKW 2s. In AWM 7 we have extended the redshift sampleto R~18 in the cluster center. We have identified 704 cluster members in17 clusters; 201 are newly identified. We summarize the kinematics anddistributions of the cluster galaxies and provide an initial discussionof substructure, mass and luminosity segregation, spectral segregation,velocity-dispersion profiles, and the relation of the central galaxy toglobal cluster properties. We compute optical mass estimates, which wecompare with X-ray mass determinations from the literature. The clustersare in a variety of dynamical states, reflected in the three classes ofbehavior of the velocity-dispersion profile in the core: rising,falling, or flat/ambiguous. The velocity dispersion of the emission-linegalaxy population significantly exceeds that of the absorption-linegalaxies in almost all of the clusters, and the presence ofemission-line galaxies at small projected radii suggests continuinginfall of galaxies onto the clusters. The presence of a cD galaxy doesnot constrain the global cluster properties; these clusters are similarto other poor clusters that contain no cD. We use the similarity of thevelocity-dispersion profiles at small radii and the cD-like galaxies'internal velocity dispersions to argue that cD formation is a localphenomenon. Our sample establishes an empirical observational baselineof poor clusters for comparison with simulations of similar systems.Observations reported in this paper were obtained at the Multiple MirrorTelescope Observatory, a facility operated jointly by the University ofArizona and the Smithsonian Institution; at the Whipple Observatory, afacility operated jointly by the Smithsonian Astrophysical Observatoryand Harvard University; and at the WIYN Observatory, a joint facility ofthe University of Wisconsin-Madison, Indiana University, YaleUniversity, and the National Optical Astronomy Observatories.
| Hα surface photometry of galaxies in the Virgo cluster. IV. The current star formation in nearby clusters of galaxies
Hα +[NII] imaging observations of 369 late-type (spiral) galaxiesin the Virgo cluster and in the Coma/A1367 supercluster are analyzed,covering 3 rich nearby clusters (A1367, Coma and Virgo) and nearlyisolated galaxies in the Great-Wall. They constitute an opticallyselected sample (mp<16.0) observed with ~ 60 %completeness. These observations provide us with the current(T<107 yrs) star formation properties of galaxies that westudy as a function of the clustercentric projected distances (Theta ).The expected decrease of the star formation rate (SFR), as traced by theHα EW, with decreasing Theta is found only when galaxies brighterthan Mp ~ -19.5 are considered. Fainter objects show no orreverse trends. We also include in our analysis Near Infrared data,providing information on the old (T>109 yrs) stars. Puttogether, the young and the old stellar indicators give the ratio ofcurrently formed stars over the stars formed in the past, or``birthrate'' parameter b. For the considered galaxies we also determinethe ``global gas content'' combining HI with CO observations. We definethe ``gas deficiency'' parameter as the logarithmic difference betweenthe gas content of isolated galaxies of a given Hubble type and themeasured gas content. For the isolated objects we find that b decreaseswith increasing NIR luminosity. In other words less massive galaxies arecurrently forming stars at a higher rate than their giant counterpartswhich experienced most of their star formation activity at earliercosmological epochs. The gas-deficient objects, primarily members of theVirgo cluster, have a birthrate significantly lower than the isolatedobjects with normal gas content and of similar NIR luminosity. Thisindicates that the current star formation is regulated by the gaseouscontent of spirals. Whatever mechanism (most plausibly ram-pressurestripping) is responsible for the pattern of gas deficiency observed inspiral galaxies members of rich clusters, it also produces the observedquenching of the current star formation. A significant fraction of gas``healthy'' (i.e. with a gas deficiency parameter less than 0.4) andcurrently star forming galaxies is unexpectedly found projected near thecenter of the Virgo cluster. Their average Tully-Fisher distance isfound approximately one magnitude further away (muo = 31.77)than the distance of their gas-deficient counterparts (muo =30.85), suggesting that the gas healthy objects belong to a cloudprojected onto the cluster center, but in fact lying a few Mpc behindVirgo, thus unaffected by the dense IGM of the cluster. Based onobservations taken at the Observatorio Astronómico Nacional(Mexico), the OHP (France), Calar Alto and NOT (Spain) observatories.Table \ref{tab4} is only available in electronic form athttp://www.edpsciences.org
| A Subarcsecond Resolution Near-Infrared Study of Seyfert and ``Normal'' Galaxies. II. Morphology
We present a detailed study of the bar fraction in the CfA sample ofSeyfert galaxies and in a carefully selected control sample of nonactivegalaxies to investigate the relation between the presence of bars and ofnuclear activity. To avoid the problems related to bar classification inthe Third Reference Catalogue (RC3), e.g., subjectivity, low resolution,and contamination by dust, we have developed an objective barclassification method, which we conservatively apply to our newsubarcsecond resolution near-infrared (NIR) imaging data set discussedin the first paper in this series. We are able to use stringent criteriabased on radial profiles of ellipticity and major axis position angle todetermine the presence of a bar and its axial ratio. Concentrating onnoninteracting galaxies in our sample for which morphologicalinformation can be obtained, we find that Seyfert hosts are barred moreoften (79%+/-7.5%) than the nonactive galaxies in our control sample(59%+/-9%), a result which is at the ~2.5 σ significance level.The fraction of nonaxisymmetric hosts becomes even larger wheninteracting galaxies are taken into account. We discuss the implicationsof this result for the fueling of central activity by large-scale bars.This paper improves on previous work by means of imaging at higherspatial resolution and by the use of a set of stringent criteria for barpresence and confirms that the use of NIR is superior to optical imagingfor detection of bars in disk galaxies.
| 1.65 μm (H-band) surface photometry of galaxies. V. Profile decomposition of 1157 galaxies
We present near-infrared H-band (1.65 μm) surface brightness profiledecomposition for 1157 galaxies in five nearby clusters of galaxies:Coma, A1367, Virgo, A262 and Cancer, and in the bridge between Coma andA1367 in the ``Great Wall". The optically selected (mpg≤16.0) sample is representative of all Hubble types, from E to Irr+BCD,except dE and of significantly different environments, spanning fromisolated regions to rich clusters of galaxies. We model the surfacebrightness profiles with a de Vaucouleurs r1/4 law (dV), withan exponential disk law (E), or with a combination of the two (B+D).From the fitted quantities we derive the H band effective surfacebrightness (μe) and radius (re) of each component, theasymptotic magnitude HT and the light concentration indexC31. We find that: i) Less than 50% of the Ellipticalgalaxies have pure dV profiles. The majority of E to Sb galaxies is bestrepresented by a B+D profile. All Scd to BCD galaxies have pureexponential profiles. ii) The type of decomposition is a strong functionof the total H band luminosity (mass), independent of the Hubbleclassification: the fraction of pure exponential decompositionsdecreases with increasing luminosity, that of B+D increases withluminosity. Pure dV profiles are absent in the low luminosity rangeLH<1010 L\odot and become dominantabove 1011 L\odot . Based on observations taken atTIRGO, Gornergrat, Switzerland (operated by CAISMI-CNR, Arcetri,Firenze, Italy) and at the Calar Alto Observatory (operated by theMax-Planck-Institut für Astronomie (Heidelberg) jointly with theSpanish National Commission for Astronomy). Table 2 and Figs. 2, 3, 4are available in their entirety only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| 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.
| A Subarcsecond-Resolution Near-Infrared Study of Seyfert and ``Normal'' Galaxies. I. Imaging Data
We present new high-resolution near-infrared observations in the J, H,and K bands, obtained to study the properties of Seyfert host galaxies.The data set consists of images in the three bands of practically theentire CfA sample of Seyfert galaxies, and K-band images of a controlsample of nonactive, ``normal,'' galaxies, matched to the Seyfert samplein the distribution of type and inclination. The spatial resolution andsampling of the new images is a factor of 2 better than previouslypublished K-band data. In this paper, we present the data in the form ofprofiles of surface brightness and color, ellipticity and major axisposition angle, as well as gray-scale maps of surface brightness in H orK and both J-H and H-K colors. We compare our surface brightness andcolor profiles with the literature and find good agreement. Our data arediscussed in detail in three subsequent publications, where we analyzethe morphologies of Seyfert and normal hosts, quantify the strength ofnonaxisymmetric features in disks and their relationship to nuclearactivity, address the question of bar fraction in Seyferts and normalgalaxies, and analyze the color information in the framework of emissionmechanisms in Seyfert 1's and 2's and in nonactive galaxies.
| The Star Formation Properties of Disk Galaxies: Hα Imaging of Galaxies in the Coma Supercluster
We present integrated Hα measurements obtained from imagingobservations of 98 late-type galaxies, primarily selected in the Comasupercluster. These data, combined with Hα photometry from theliterature, include a magnitude-selected sample of spiral (Sa to Irr)galaxies belonging to the ``Great Wall'' complete up to m_p = 15.4, andthus composed of galaxies brighter than M_p = -18.8 (H_0 = 100 km s^-1Mpc^-1). The frequency distribution of the Hα equivalent width,determined for the first time from an optically complete sample, isapproximately Gaussian, peaking at EW ~ 25 Å. We find that, at thepresent limiting luminosity, the star formation properties of spiral +Irr galaxy members of the Coma and A1367 Clusters do not differsignificantly from those of the isolated ones belonging to the GreatWall. The present analysis confirms the well-known increase of thecurrent massive star formation rate (SFR) with Hubble type. Moreover,perhaps a more fundamental anticorrelation exists between the SFR andthe mass of disk galaxies: low-mass spirals and dwarf systems havepresent SFRs ~50 times higher than giant spirals. This result isconsistent with the idea that disk galaxies are coeval, evolving as``closed systems'' with exponentially declining SFR, and that the massof their progenitor protogalaxies is the principal parameter governingtheir evolution. Massive systems having high initial efficiency ofcollapse, or a short collapse timescale, have retained little gas tofeed the present epoch of star formation. These findings support theconclusions of Gavazzi & Scodeggio, who studied the color-massrelation of a local galaxy sample, and agree with the analysis by Cowieet al., who traced the star formation history of galaxies up to z >1. Based on observations made at the Observatorio AstronómicoNacional (OAN), San Pedro Mártir, B.C., of the UniversidadNacional Autónoma de México (UNAM).
| 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 molecular gas content of spiral galaxies in the Coma/A1367 supercluster.
We present ^12^CO(J=1-0) line observations of 73 spiral galaxies mostlyin the Coma/A1367 supercluster. From these data, combined with dataavailable in the literature, we extract the first complete, opticallyselected sample (m_pg_<15.2) of 37 isolated and of 27 clustergalaxies. Adopting a standard conversion factor X=N(H_2_)/I(CO), weestimate that the molecular hydrogen content of isolated spiral galaxiesis, on average, 20% of the atomic hydrogen reservoir, significantlylower than previous estimates based on samples selected by FIR criteria,thus biased towards CO rich objects. We show that the frequencydistributions of the CO deficiency parameter, defined as the differencebetween the expected and the observed molecular gas content of a galaxyof given luminosity (or linear diameter), computed separately forcluster and isolated galaxies, are not significantly different,indicating that the environment does not affect the molecular gascontent of spiral discs. A well defined relationship exists betweenM_i_(H_2_) and the star formation activity in bright galaxies, while itis weaker at lower luminosities. We interpret this finding as indicatingthat CO emission traces relatively well the H_2_ mass only in high-massgalaxies, such as the Milky Way. On the other hand, in low-mass spiralsthe higher far-UV radiation field produced by young O-B stars and thelower metallicity cause the photodissociation of the diffuse moleculargas, weakening the expected relationship between star formation and theCO emission. The conversion factor between the CO line intensity and theamount of molecular hydrogen being ill-determined and variable with theUV flux and abundances, it is difficult to assess the relationshipbetween the star formation and the amount of molecular hydrogen.
| 1.65 μm (H-band) surface photometry of disk galaxies. I. Observations of 158 galaxies with the Calar Alto 2.2 M telescope.
Near Infrared (H-band) surface photometry of 158 (mostly) disk galaxiesbelonging to the Coma Supercluster and to the A262 and Cancer clusterswas obtained using the 256^2^ NICMOS3 array MAGIC attached to the 2.2mCalar Alto telescope. Magnitudes and diameters within the21.5mag/arcsec^2^ isophote, concentration indices and total H magnitudesare derived.
| The Hubble Diagram for Supernovae of Type Ia. II. The Effect on the Hubble Constant of a Correlation between Absolute Magnitude and Light Decay Rate
New Hubble diagrams in B and V are derived for supernovae of type Ibased on light curves from the archive literature plus 13 new lightcurves with superior modern photometry observed in the CerroTololo/University of Chile program (Hamuy et al, 1995). The sample isrestricted to SNe Ia whose light curves are defined by photometrybeginning 5 days or less after maximum light and with (B - V)max <0.5 mag. Supernovae of known type Ib or Ic are also excluded. Theresulting Hubble diagrams, extending to redshifts of 30,00 km s^- 1^,have dispersions in absolute magnitude of 0.34 mag in B and 0.33 mag inV, confirming that spectroscopically "normal" (Branch et al. 1993) SNeIa are among the best standard candles known. A solution for the slopeof the Hubble diagram gives n(B) = 0.977 +/- 0.025 and n(V) = 1.020 +/-0.024 for the exponent in ν~D^n^, proving linearity of the expansionfield to a high level. The residuals in magnitude from the ridge line ofthe Hubble diagram are compared with the light decay rate during thefirst 15 days to test the correlation between the two suggested byPskovskii and by Phillips. The strongest possible correlation using theextant data has a slope 3 times smaller than that derived by Phillips,and 2 times smaller than suggested by Hamuy et al., leading to adecrease of less than 10% in the distance scale based on the present(1995) SNe Ia calibration by means of three supernovae whose distancesare known from Cepheids in their parent galaxies. Applying the maximumpossible correction to M(max) for a Psko'vskii- Phillips effect wouldgive Hubble constants of H_0_(B)<= 54 +/- 4 km s^-1^ Mpc^-1^, andH_0_(V) <= 59 +/- 4 km s^-1^ Mpc^-1^, where the errors are internal.It is argued that the absence of measurable bias effects in the Hubblediagrams shows that the three local (nearest) SNe Ia presentlycalibrated via Cepheid distances cannot all be overluminous relative tothe average of more distant SNe. If they are underluminous, which mustbe the case by the statistics of the Malmquist effect if the largedispersion in M(max) for SNe Ia claimed by Hamuy et al. applies to thecalibrators, then the value of H_0_ = 52 km s^-1^ Mpc^-1^ given by Sahaet al. is an upper limit to the Hubble constant.
| The blue anbd visual absolute magnitude distributions of Type IA supernovae
Tully-Fisher (TF), surface brightness fluctuation (SBF), and Hubble lawdistances to the parent galaxies of Type Ia supernovae (SNs Ia) are usedin order to study the SN Ia blue and visual peak absolute magnitude(MB and MV) distributions. We propose twoobjective cuts, each of which produces a subsample with small intrinsicdispersion in M. One cut, which can be applied to either band,distinguishes between a subsample of bright events and a smallersubsample of dim events, some of which were extinquished in the parentgalaxy and some of which were intrinsically subluminous. The brightevents are found to be distributed with an observed dispersions of 0.3less than or approximately = Sigmaobs less than orapproximately = 0.4 about a mean absolut magnitude (M-barB orM-barV). Each of the dim SNs was spectroscopically peculiarand/or had a red B-V color; this motivates the adoption of analternative cut that is based on B-V rather than on M. To wit, SNs Iathat are both known to have -0.25 less than B-V less than + 0.25 and notknown to be spectroscopically peculiar show observational dispersion ofonly Sigmaobs(MB) =Sigmaobs(MV) = 0.3. Because characteristicsobservational errors produce Sigmaerr(M) greater than 0.2,theintrinsic dispersion among such SNs Ia is Sigmaint(M) lessthan or approximately = 0.2. The small observational dispersionindicates that SNs Ia, the TF relation, and SBFs all good relativedistances to those galaxies that produce SNs Ia. The conflict betweenthose who use SNs Ia in order to determine the value of the Hubbleconstant (H0) and those who use TF and SBF distances todetermine H0 results from discrepant calibrations.
| Colors, luminosities, and masses of disk galaxies. 2: Environmental dependenceis
The B-band and near-infrared (H) luminosity functions of spiral galaxiesare derived for the Coma and A1367 clusters and for a referencepopulation of 'field' galaxies in the Coma supercluster. They areconsistent at the bright end, but they differ significantly at the faintend, indicating an overdensity of spirals with blue color (B-H less than3.0) and faint H luminosity (H greater than -21.5) in clusters withrespect to the field. These objects have disturbed morphology andpeculiar velocities significantly larger than the rest of the clustersample. We discuss these results in the framework of a possibleenvironmental dependence of galaxy evolution, and we conclude thatenhanced current star formation in cluster spiral galaxies might occurdue to molecular gas collapse stimulated by the ram-pressure mechanism.
| Kinematics and dynamics of the MKW/AWM poor clusters
We report 472 new redshifts for 416 galaxies in the regions of the 23poor clusters of galaxies originally identified by Morgan, Kayser, andWhite (MKW), and Albert, White, and Morgan (AWM). Eighteen of the poorclusters now have 10 or more available redshifts within 1.5/h Mpc of thecentral galaxy; 11 clusters have at least 20 available redshifts. Basedon the 21 clusters for which we have sufficient velocity information,the median velocity scale is 336 km/s, a factor of 2 smaller than foundfor rich clusters. Several of the poor clusters exhibit complex velocitydistributions due to the presence of nearby clumps of galaxies. We checkon the velocity of the dominant galaxy in each poor cluster relative tothe remaining cluster members. Significantly high relative velocities ofthe dominant galaxy are found in only 4 of 21 poor clusters, 3 of whichwe suspect are due to contamination of the parent velocity distribution.Several statistical tests indicate that the D/cD galaxies are at thekinematic centers of the parent poor cluster velocity distributions.Mass-to-light ratios for 13 of the 15 poor clusters for which we havethe required data are in the range 50 less than or = M/LB(0)less than or = 200 solar mass/solar luminosity. The complex nature ofthe regions surrounding many of the poor clusters suggests that thesegroupings may represent an early epoch of cluster formation. Forexample, the poor clusters MKW7 and MKWS are shown to be gravitationallybound and likely to merge to form a richer cluster within the nextseveral Gyrs. Eight of the nine other poor clusters for which simpletwo-body dynamical models can be carried out are consistent with beingbound to other clumps in their vicinity. Additional complex systems withmore than two gravitationally bound clumps are observed among the poorclusters.
| A CCD survey of galaxies. III. Observations with the Loiano 1.5m telescope.
Continuing a CCD survey of galaxies belonging or projected onto the Comaand Hercules Superclusters and to the A262, Virgo and Cancer clusters,we present isophote maps and photometric profiles in the Johnson systemof 127 galaxies (126 taken in the V, 28 of which also in the B band, oneonly in B). For the objects in common we compare our results with thosein the RC3.
| Type IA supernovae as standard candles
The distribution of absolute blue magnitudes among Type Ia supernovae(SNs Ia) is studied. Supernovae were used with well determined apparentmagnitudes at maximum light and parent galaxies with relative distancesdetermined by the Tully-Fisher or Dn - sigma techniques. The meanabsolute blue magnitude is given and the observational dispersion isonly sigma(MB) 0.36, comparable to the expected combined errors indistance, apparent magnitude, and extinction. The mean (B-V) color atmaximum light is 0.03 +/- 0.04, with a dispersion sigma(B-V) = 0.20. TheCepheid-based distance to IC 4182, the parent galaxy of the normal andunextinguished Type Ia SN 1937C, leads to a Hubble constant of H(0) + 51+/- 12 km/s Mpc. The existence of a few SNs Ia that appear to have beenreddened and dimmed by dust in their parent galaxies does not seriouslycompromise the use of SNs Ia as distance indicators.
| The rate of supernovae. I - The data base, the recipe and the uncertainties
Because the determination of SN rates is vulnerable to the small numberstatistics of homogeneous samples, the data bases of two independent SNsearches were merged in order to build up the largest data base everused for SN rate determinations. Using a software specially developedfor the analysis of these materials, the individual control times wereestimated for each galaxy and in turn the SN rates for samples ofgalaxies extracted from different catalogs were estimated. Theuncertainties in the input parameters were quantitatively estimated byseveral tests. It is found that the assumption of the limiting discoverymagnitude is crucial. Contrary to previous belief, it is shown that thedispersion of the absolute SN magnitude at maximum is not particularlyimportant for the SN rates determined from the samples, whereasuncertainties about the shape of the light curve are more serious. Therate of SNe was computed for four galaxy samples extracted fromdifferent catalogs. It is shown that the SNe rate reflects thedifferences among the galaxy parameters reported by different catalogs.
| 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.
| Supernova studies. I - A catalogue of magnitude observations of supernovae I
A catalog of photometric observations (UBV or pg) of 81 supernovae oftype I is presented. Only supernovae with multiple data were included.
| Near-infrared observations of galaxies in the Coma supercluster
Near-IR magnitudes have been obtained for 136 galaxies in the Coma/A1367supercluster region, and near-IR colors (J-H) and (H-K) for 90 and 87objects, respectively. The near-IR colors are contained in a small rangeand do not depend on morphological types, galaxy inclination, orenvironment. Optical-to-IR colors depend strongly on a galaxy'smorphological type and inclination. There is a dependence of therelative excess of radio, and to a lesser degree, of far-IR emission onrecent star formation activity. The magnitude-line width relation forgalaxies in Coma and A1367 obtained with these data has a larger spreadthan previously found with smaller samples. The data suggest a distancemodulus to Coma of about 35, regardless of the choice of primarycalibrators.
| The Asiago Supernova Catalogue
A Catalogue of Supernovae (SNe) is presented which tabulates the maindata relative to all extragalactic SNe discovered up to 1988 December31, and to their parent galaxies. In total 661 SNe are listed of which267 are classified. For an easier consultation, two lists are givenwhere the SNe are ordered chronologically and by Right Ascension,respectively. The overall distribution of classified supernovae over themorphological types of their parent galaxies is also presented in asummary table.
| Forbidden O III emission in two magnitude-limited field-galaxy surveys
The paper presents emission-line strengths for 394 galaxies from thefield-galaxy redshift surveys of Kirshner, Oemler, and Schechter (1978)and Kirshner et al. (1983) as part of a study of the nature of field andvoid galaxies. These data are 95 percent complete in their coverage ofthe forbidden O III 5007, 4959 A emission lines. It is found that 8.8 +or - 1.5 percent of a J magnitude-limited data set have forbidden O III5007 A emission equivalent widths greater than 10 A. There is noevidence that the spatial distribution of emission-line galaxies in eachfield differs from that of galaxies without emission. However, there isa significant increase in the fraction of galaxies with strong forbiddenO III emission in the southern fields of the Kirshner, Oemler, andSchechter (1978) survey as compared with the other survey fields. Theresults are consistent with the conclusion that the fraction of galaxieswith emission is larger in the Bootes void than in the general field,but tighter constraints on the void normal galaxy population are neededto improve the statistics.
| H I survey of face-on galaxies - The frequency of distortions in H I disks
The full results of an H I survey of face-on galaxies are presented andit is shown that narrow H I profiles are rare in normal spiral galaxies.This is due in part to the wider-than-expected range of the integraldispersion and in part to the frequent occurrence of large-scaledistortions in the H I disk. These factors reduce the number of galaxieswith half-power widths less than 30 km/s to about 24 percent of thosethat would occur if galaxies generally had quiescent, coplanar H Idisks. Two useful subsets may be drawn from this study of 212 face-ongalaxies with axial ratios greater than 0.87. Fifty-two spirals of allmorphological types have half-power widths smaller than 100 km/s and maybe used for studies that benefit from a small velocity spread and anenhanced beam-filling factor. About 40 galaxies have velocity widthsmuch larger than expected and are of interest in studies of dynamicallypeculiar systems.
| 21 centimeter study of spiral galaxies in the Coma supercluster
High-sensitivity, 21 cm line observations of 130 galaxies in theComa/A1367 Supercluster region are presented and used to study thelarge-scale distribution of galaxies in the direction of the ComaSupercluster and the H I content in spiral galaxies as a function of thelocal galaxy density. Groups of galaxies are found to form aquasi-continuous structure that connects the Local Supercluster to theComa Supercluster. This structure is composed of real filaments only inthe vicinity of the Coma Cluster. Spiral galaxies in the surveyed groupsand multiple systems have H I content not dissimilar from that ofisolated galaxies. Galaxies within about 1 Abell radius from the ComaCluster contain about three times less hydrogen on average than isolatedgalaxies. There is a strong tendency for galaxies that are more severelyH I-depleted to be redder and of earlier Hubble type. In the ComaCluster a considerable fraction of late-type, blue galaxies have largedeficiency parameters.
| Light and colour curves of type I and II supernovae.
Not Available
| Taxonomical analysis of superclusters. II - The A1367/Coma supercluster
The nonhierarchical taxonomical method has been applied to a sample of185 galaxies, complete to m not greater than 15, in the A1367/Comaregion. Once the fore- and background galaxies have been identified, theanalysis of the A1367 cluster shows it composed by two gravitationallybound clumps at essentially the same redshift, 6396 km/s and 6562 km/s,respectively. Central Coma is traced by three different groups whosegravitational binding does not appear clearly. However, accepting theunique dynamical entity of Central Coma, some other neighboring groupswould be part of the cluster. In that case, the average radial velocityand dispersion of the Coma cluster would be 7013 and 423 km/s,respectively. The M/L ratios for the groups evidenced by the taxonomyrange from 13 to 170. The missing mass problem only appears when all thegalaxies in the sample are considered as members of a unique dynamicalstructure. The relationship found in other systems between the redshift,the morphological type and the radioemissivity is also present in thesample.
| A Checklist of Supernovae in the NGC and IC Galaxies Through 1985
This Checklist of Supernovae in the NGC and IC Galaxies Through 1985 ispresented to assist those interested in undertaking a visual orphotographic search for extragalactic supernovae. Some galaxies appearto have had more than one or two supernovae, and these should bemonitored closely for any new outbursts.
| Radio continuum survey of the Coma/A1367 supercluster. II - 1.5 GHz observations of 396 CGCG galaxies
1.5 GHz VLA radio continuum observations of 396 relatively isolated CGCGgalaxies in the Coma/A1367 supercluster yielded the detection of 95objects. These observations, added to the ones presented in previouspapers, form a complete sample of optically selected objects with m(p)equal to or less than 15.3. Two wide-angle-tailed sources have beenfound in smaller groups within the supercluster.
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