Classifications of the Host Galaxies of Supernovae, Set III
A homogeneous sample comprising host galaxies of 604 recent supernovae,including 212 objects discovered primarily in 2003 and 2004, has beenclassified on the David Dunlap Observatory system. Most SN 1991bg-likeSNe Ia occur in E and E/Sa galaxies, whereas the majority of SN1991T-like SNe Ia occur in intermediate-type galaxies. This differenceis significant at the 99.9% level. As expected, all types of SNe II arerare in early-type galaxies, whereas normal SNe Ia occur in all Hubbletypes. This difference is significant at the 99.99% level. A smallnumber of SNe II in E galaxies might be due to galaxy classificationerrors or to a small young-population component in these mainly oldobjects. No significant difference is found between the distributionsover the Hubble type of SNe Ibc and SNe II. This confirms that both ofthese types of objects have similar (massive) progenitors. The presentdata show that in order to understand the dependence of supernova typeon host-galaxy population, it is more important to obtain accuratemorphological classifications than it is to increase the size of thedata sample.
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Supernova 2003gt in NGC 6930
IAUC 8172 available at Central Bureau for Astronomical Telegrams.
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Small-Scale Systems of Galaxies. I. Photometric and Spectroscopic Properties of Members
This paper is the first of a series addressed to the investigation ofgalaxy formation/evolution in small-scale systems of galaxies (SSSGs),which are located in low-density cosmic environments. Our algorithm forSSSG selection includes galaxy systems of two or more galaxies lyingwithin Δcz<=1000 km s-1 and a 200h-1100 kpc radius volume. We present the analysisof the photometric and spectroscopic properties of 19 member galaxiesbelonging to a sample of 11 SSSGs. In the μe-replane early-type members may be considered ``ordinary,'' rather than``bright,'' galaxies, with a significant fraction of galaxies having adisk or disky isophotes. We do not detect fine structure or signaturesof recent interaction events in the early-type galaxy population, apicture also confirmed by the spectroscopy. At odds with these findingsare several spiral members with open arm configurations, as expected ininteracting systems. At the same time, emission lines in the spectra ofspiral members fall in the H II regions regime. None of the objectsdisplays unambiguous indications of nuclear activity, although fourspiral nuclei could be ascribed to the class of Seyferts. The starformation rate seems enhanced over the average expected in spiralgalaxies only for poorer SSSGs in particular pairs (<=50Msolar yr-1) but without being in the range ofstarburst systems.Based on observations obtained at the European Southern Observatory, LaSilla, Chile (program No. 57.B-036).
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Catalogue of HI maps of galaxies. I.
A catalogue is presented of galaxies having large-scale observations inthe HI line. This catalogue collects from the literature the informationthat characterizes the observations in the 21-cm line and the way thatthese data were presented by means of maps, graphics and tables, forshowing the distribution and kinematics of the gas. It containsfurthermore a measure of the HI extension that is detected at the levelof the maximum sensitivity reached in the observations. This catalogueis intended as a guide for references on the HI maps published in theliterature from 1953 to 1995 and is the basis for the analysis of thedata presented in Paper II. The catalogue is only available inelectronic form at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
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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.
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Photoelectric UBV Photometry of 179 Bright Galaxies
This paper presents photoelectric UBV multiaperture photometry of 179bright galaxies that was used to compute total magnitudes and colorindices published in the Third Reference Catalog of Bright Galaxies(RC3). The observations were made at the McDonald Observatory from 1983December to 1986 September with an Amperex 56-DVP photometer attached tothe 0.76 and 0.91 m telescopes. The observations can also be used tocalibrate CCD images.
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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.
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Observations of galaxies in groups at 102 MHz
Observations of 325 galaxies in groups were carried out at a frequencyof 102 MHz via the scintillation method. Radio emission was found in 42of these components. Eleven of these have a meridional component.
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Uncertainties in 21 centimeter redshifts. I - Data
High-precision data on the 21-cm redshifts, profile widths, and shapesfor 625 galaxies are presented. Each galaxy is listed in across-identification and morphology table. High-resolution spectra arealso given for each galaxy. Internal redshift consistency is roughly 1km/s for galaxies for which the S/N is above 15. No systematic effectshave been found which might influence the observed redshift quantizationat 72.5 km/s or its submultiples.
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An Arecibo survey for extragalactic hydroxyl absorption. I - Presentation of results
Hydroxyl absorption has been detected in a total of 24 galaxies;megamaser emission in six additional galaxies brings the total number ofdetections of extragalactic OH to 30. About 50 percent of theextragalactic absorption lines are asymmetrically skewed toward the red,indicating that the molecular disks could have an unusual velocity orexcitation structure. The hyperfine ratio for the 1667 and 1665 MHztransitions in most galaxies lies within the limits specified by LTEconditions.
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The Malmquist bias and the value of H0 from the Tully-Fisher relation
A large sample (n = 395) of spiral (Sab to Sd type) galaxies havingcorrected apparent magnitudes B-zero-sub-T and 21-cm line data (HI linewidths and radial velocities) is used to investigate in a new way theinfluence of the Malmquist bias on the determination of theextragalactic distance scale and the Hubble constant derived from theapplication of the B-band Tully-Fisher relation. This effect is clearlyidentified by using relative kinematic distances derived from aclassical local velocity field model and the concept of normalizedrelative kinematic distance. It results in an unbiased estimate of theHubble constant H0 which appears quite insensitive to the parameters(mean velocity of Virgo and infall velocity of the Local Group towardVirgo) adapted for the local velocity field model. A similar effect isfound from a sample of galaxies (n = 72) which are 'sosies' of 14primary galaxies. It is suggested that the presently derived H0represents the global value of the Hubble constant.
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Investigation of the Galaxies from the Byurakan Classification at a Frequency of 102-MHZ
Not Available
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An apparent increase of the Hubble constant with velocities of the determining galaxies
A study is conducted of the variation of the Hubble constant derivedfrom the Bottinelli et al. (1983) version of the Tully-Fisher relationwith respect to kinematic distances D(v) in an infall model towardVirgo. The sample of 256 galaxies used encompasses types Sab to Sd. Itis noted that, before or after correction of the type effect, the Hubbleconstant increases from approximately log H(0) of 1.78 at D(v) of 250km/sec to 2.08 at 5000 km/sec. Attention is given to such differentpossible explanations for this as galactic extinction, the Malmquistbias, TF relation slope, and an inadequate model.
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Enhanced radio emission in binary spiral galaxies
A comparison is conducted between the radio emission characteristics ofa sample of isolated pairs of spiral galaxies and those of a sample ofisolated spiral galaxies for which complete distance information isavailable. It is noted that double galaxy total emission is, on average,a factor of 2 more powerful than that of isolated spiral galaxies ofcomparable luminosity. The radio emission enhancement in these doublegalaxies is correlated with a tidal index, in keeping with a tidalorigin for the enhancement.
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H I line studies of galaxies. III - Distance moduli of 822 disk galaxies
The distance scale established on the basis of a distance moduli catalog(for 822 galaxies) that was derived from 21-cm line widths via theB-band Tully-Fisher relation is compared with several independent scaleshaving a common zero point, that are based on the indicators forluminosity index, redshift, ring diameters, brightest superassociations,and effective diameters. These are in excellent systematic agreement,and confirm the linearity of the H I scale in the 24-35 modulusinterval, but indicate a small systematic zero point difference of about0.2 mag, which must be added to the H I moduli to place them on the same'short' distance scale defined by the others.
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A catalogue of HI diameters for 238 galaxies
A large catalog of effective H I diameters for 238 galaxies has beencompiled from new measurements made with the Nancay radiotelescope (40percent of the catalog), and previously published diameters homogenizedto the same definition. A good covering both in morphological types andin luminosity within each type is thus achieved.
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21-CM Line Profiles of 40 SA Spiral Galaxies
Not Available
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Neutral hydrogen study of 40 SA spiral galaxies
Results of a neutral hydrogen 21-cm line study of 40 Sa spiral galaxieswith apparent magnitudes from 10.5 to 14.5, recession velocities lowerthan 6500 km/s and intrinsic luminosities from 1 to 40 x 10 to the 9thsolar units are presented. The galaxies are found to form a ratherhomogeneous class, with a relative H I content smaller than that oflater spirals and an indicative total mass to luminosity ratio higherthan that of later galaxies of the same luminosity. The indicative totalmass is also observed to be well correlated to the luminosity, allowingit to be used as a sensitive distance criterion. A linear correlationbetween the log of the internal velocity spread and the log of theluminosity is obtained; internal velocity spread is also found to dependon galaxy type. Finally, it is observed that the Sa spirals are on themean five times richer in hydrogen than the hydrogen-rich ellipticalsand at least ten times richer than hydrogen-poor ellipticals, supportingthe distinction between the two types of elliptical galaxies.
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Photographs of nebulae with the 60-inch reflector, 1917-1919.
Not Available
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