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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.
| Near-infrared observations of galaxies in Pisces-Perseus. V. On the origin of bulges
We investigate the scaling relations of bulge and disk structuralparameters for a sample of 108 disk galaxies. Structural parameters ofindividual galaxies are obtained from two-dimensional bulge/diskdecomposition of their H-band surface brightness distributions. Bulgesare modelled with a generalized exponential (Sérsic) withvariable integer shape index n. We find that bulge effectivescalelengths reB and luminosity MBincrease with increasing n, but disk properties are independent of bulgeshape. As Hubble type T increases, bulges become less luminous and theirmean effective surface brightness <μeB>gets fainter; disk <μeD> shows a similar,but much weaker, trend. When bulge parameters(<μeB>, reB,MB) are compared with disk ones(<μeD>, reD,MD), they are tightly correlated for n=1 bulges. Thecorrelations gradually worsen with increasing n such that n=4 bulgesappear virtually independent of their disks. The Kormendy relation,<μeB> vs. reB, isshown to depend on bulge shape n; the two parameters are tightlycorrelated in n=4 bulges (r=0.8), and increasingly less so as ndecreases; disk <μeD> andreD are well correlated (r=0.7). Bulge-to-disksize ratios reB/reD areindependent of Hubble type, but smaller for exponential bulges; the meanreB/reD for n=1 bulges is 4times smaller than that for n=4, with a spread which is 9 times smaller.Strongly barred SB galaxies with exponential bulges are more luminousthan their unbarred counterparts. Exponential bulges appear to beclosely related to their underlying disks, while bulges with higher nvalues are less so; n=4 bulges and their disks apparently have norelation. We interpret our results as being most consistent with asecular evolutionary scenario, in which dissipative processes in thedisk are responsible for building up the bulges in most spirals.Based on observations at the TIRGO, NOT, and VATT telescopes. TIRGO(Gornergrat, CH) is operated by IRA-CNR, Arcetri, Firenze. NOT (LaPalma, Canary Islands) is operated by NOTSA, the Nordic ObservatoryScientific Association. VATT (Mt. Graham, AZ) is operated by VORG, theVatican Observatory Research Group.Full Table 1 is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/414/905.
| Supernova 2003ja in NGC 846
IAUC 8231 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.
| Near-infrared observations of galaxies in Pisces-Perseus. I. vec H-band surface photometry of 174 spiral
We present near-infrared, H-band (1.65 $() μm), surface photometry of174 spiral galaxies in the area of the Pisces-Perseus supercluster. Theimages, acquired with the ARNICA camera mounted on various telescopes,are used to derive radial profiles of surface brightness, ellipticities,and position angles, together with global parameters such as H-bandmagnitudes and diameters Radial profiles in tabular form and images FITSfiles are also available upon request from gmorio@arcetri.astro.it.}.The mean relation between H-band isophotal diameter D_{21.5} and theB-band D25 implies a B-H color of the outer disk bluer than3.5; moreover, D_{21.5}/D25 depends on (global) color andabsolute luminosity. The correlations among the various photometricparameters suggest a ratio between isophotal radius D_{21.5}/2 and diskscale length of ~ m3.5 and a mean disk central brightness ~ meq 17.5H-mag arcsec^{-2}. We confirm the trend of the concentration indexC31$ with absolute luminosity and, to a lesser degree, withmorphological type. We also assess the influence of non-axisymmetricstructures on the radial profiles and on the derived parameters. Basedon observations at the TIRGO, NOT, and VATT telescopes. TIRGO(Gornergrat, CH) is operated by CAISMI-CNR, Arcetri, Firenze. NOT (LaPalma, Canary Islands) is operated by NOTSA, the Nordic ObservatoryScientific Association. VATT (Mt. Graham, Az) is operated by VORG, theVatican Observatory Research Group Table 3 and Fig. 4 are only availablein electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html.
| Visual search for galaxies near the northern crossing of the Supergalactic Plane by the Milky Way
We have visually examined 12 Palomar red plates for galaxies at lowGalactic latitude b, where the Supergalactic Plane (SGP) is crossed bythe Galactic Plane (GP), at Galactic longitude l~135 deg. The catalogueconsists of 2575 galaxy candidates, of which 462 have major axisdiameter d>=0.8 arcmin (uncorrected for extinction). Galaxycandidates can be identified down to --b--~=0 deg. One of our galaxycandidates (J24=Dwingeloo 1) has recently been discovered independentlyat 21 cm by Kraan-Korteweg et al. as a nearby galaxy. Comparisons withthe structures seen in the IRAS and UGC catalogues are made. We comparethe success rate of identifying galaxies using the IRAS Point SourceCatalogue under different colour selection criteria. The criteria thatrequire both the 60- and 100-μm fluxes to be of high quality have thehighest probability of selecting a galaxy (with d>=0.6 arcmin), butat the expense of selecting a smaller number of galaxies in total.
| 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.
| A 21 CM survey of the Pisces-Perseus supercluster. III - The region north of +38 degrees
As part of a comprehensive survey of galaxies in the region of thePisces-Perseus supercluster and its surroundings, 21-cm lineobservations obtained with the NRAO 91-m telescope are presented for 383galaxies in the right ascension range from 22 to 10 hr and north of +38deg declination. Recent improvements to the Green Bank receiver/feedsystem have dramatically raised detection rates at the distance ofPisces-Perseus (cz = +5000 km/s). The present study has contributed todouble the number of known redshifts outside rich clusters in thissection of the sky. The H I content of the current sample, as expressedin terms of the H I mass expected for a galaxy of the same optical sizeand morphology, matches the standard of normalcy established forisolated galaxies.
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