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The Hα Galaxy Survey . III. Constraints on supernova progenitors from spatial correlations with Hα emission
Aims.We attempt to constrain progenitors of the different types ofsupernovae from their spatial distributions relative to star formationregions in their host galaxies, as traced by Hα + [Nii] lineemission. Methods: .We analyse 63 supernovae which have occurredwithin galaxies from our Hα survey of the local Universe. Threestatistical tests are used, based on pixel statistics, Hα radialgrowth curves, and total galaxy emission-line fluxes. Results:.Many type II supernovae come from regions of low or zero emission lineflux, and more than would be expected if the latter accurately traceshigh-mass star formation. We interpret this excess as a 40% "Runaway"fraction in the progenitor stars. Supernovae of types Ib and Ic doappear to trace star formation activity, with a much higher fractioncoming from the centres of bright star formation regions than is thecase for the type II supernovae. Type Ia supernovae overall show a weakcorrelation with locations of current star formation, but there isevidence that a significant minority, up to about 40%, may be linked tothe young stellar population. The radial distribution of allcore-collapse supernovae (types Ib, Ic and II) closely follows that ofthe line emission and hence star formation in their host galaxies, apartfrom a central deficiency which is less marked for supernovae of typesIb and Ic than for those of type II. Core-collapse supernova ratesoverall are consistent with being proportional to galaxy totalluminosities and star formation rates; however, within this total thetype Ib and Ic supernovae show a moderate bias towards more luminoushost galaxies, and type II supernovae a slight bias towardslower-luminosity hosts.
| 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.
| The Hα galaxy survey. I. The galaxy sample, Hα narrow-band observations and star formation parameters for 334 galaxies
We discuss the selection and observations of a large sample of nearbygalaxies, which we are using to quantify the star formation activity inthe local Universe. The sample consists of 334 galaxies across allHubble types from S0/a to Im and with recession velocities of between 0and 3000 km s-1. The basic data for each galaxy are narrowband H\alpha +[NII] and R-band imaging, from which we derive starformation rates, H\alpha +[NII] equivalent widths and surfacebrightnesses, and R-band total magnitudes. A strong correlation is foundbetween total star formation rate and Hubble type, with the strongeststar formation in isolated galaxies occurring in Sc and Sbc types. Moresurprisingly, no significant trend is found between H\alpha +[NII]equivalent width and galaxy R-band luminosity. More detailed analyses ofthe data set presented here will be described in subsequent papers.Based on observations made with the Jacobus Kapteyn Telescope operatedon the island of La Palma by the Isaac Newton Group in the SpanishObservatorio del Roque de los Muchachos of the Instituto deAstrofísica de Canarias.The full version of Table \ref{tab3} is available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/414/23 Reduced image datafor this survey can be downloaded fromhttp://www.astro.livjm.ac.uk/HaGS/
| Classifications of the Host Galaxies of Supernovae, Set II
Classifications on the DDO system are given for an additional 231 hostgalaxies of supernovae that have been discovered during the course ofthe Lick Observatory Supernova Search with the Katzman Automatic ImagingTelescope (KAIT). This brings the total number of hosts of supernovae(SNe) discovered (or independently rediscovered) by KAIT, which have sofar been classified on a homogeneous system, to 408. The probabilitythat SNe Ia and SNe II have a different distribution of host-galaxyHubble types is found to be 99.7%. A significant difference is alsofound between the distributions of the host galaxies of SNe Ia and ofSNe Ibc (defined here to include SNe Ib, Ib/c, and Ic). However, nosignificant difference is detected between the frequency distributionsof the host galaxies of SNe II and SNe IIn. This suggests that SNe IInare generally not SNe Ia embedded in circumstellar material that aremasquerading as SNe II. Furthermore, no significant difference is foundbetween the distribution of the Hubble types of the hosts of SNe Ibc andof SNe II. Additionally, SNe II-P and SNe II-L are found to occur amongsimilar stellar populations. The ratio of the number of SNe Ia-pec tonormal SNe Ia appears to be higher in early-type galaxies than it is ingalaxies of later morphological types. This suggests that the ancestorsof SNe Ia-pec may differ systematically in age or composition from theprogenitors of normal SNe Ia. Unexpectedly, five SNe of Types Ib/c, II,and IIn (all of which are thought to have massive progenitors) are foundin host galaxies that are nominally classified as types E and S0.However, in each case the galaxy classification is uncertain, or newlyinspected images show evidence suggesting a later classification. Amongthese five objects, NGC 3720, the host galaxy of SN 2002at, wasapparently misidentified in the Carnegie Atlas of Galaxies.
| Spectroscopy of KISS Emission-Line Galaxy Candidates. I. MDM Observations
Spectroscopic observations for 351 emission-line galaxy candidates fromthe KPNO International Spectroscopic Survey (KISS) have been obtainedusing the MDM Observatory 2.4 m telescope on Kitt Peak. KISS is anongoing wide-field objective-prism survey for extragalacticemission-line objects, which has cataloged over 2200 emission-linegalaxy (ELG) candidates to date. Spectroscopic follow-up observationsare being carried out to study the characteristics of the surveyobjects. The observational data presented here include redshifts,reddening estimates, line equivalent widths, Hα line fluxes, andemission-line ratios. The galaxies have been classified based on theiremission-line characteristics. The procedure for selecting the ELGcandidates in KISS is found to be very reliable: 95% of the candidatesin this sample are verified to have emission lines. A comparison ofobjective-prism survey data-redshifts, Hα line fluxes, andequivalent widths-with the long-slit measurements shows good overallagreement.
| A search for Low Surface Brightness galaxies in the near-infrared. I. Selection of the sample
A sample of about 3800 Low Surface Brightness (LSB) galaxies wasselected using the all-sky near-infrared (J, H and Ks-band)2MASS survey. The selected objects have a mean central surfacebrightness within a 5'' radius around their centre fainter than 18 magarcsec-2 in the Ks band, making them the lowestsurface brightness galaxies detected by 2MASS. A description is given ofthe relevant properties of the 2MASS survey and the LSB galaxy selectionprocedure, as well as of basic photometric properties of the selectedobjects. The latter properties are compared to those of other samples ofgalaxies, of both LSBs and ``classical'' high surface brightness (HSB)objects, which were selected in the optical. The 2MASS LSBs have aBT_c-KT colour which is on average 0.9 mag bluerthan that of HSBs from the NGC. The 2MASS sample does not appear tocontain a significant population of red objects.All tables and Figs. 2a-c are only available in electronic form athttp://www.edpsciences.org
| Supernova 2002ca in UGC 8521
IAUC 7875 available at Central Bureau for Astronomical Telegrams.
| Supernova 2002ce in NGC 2604
IAUC 7875 available at Central Bureau for Astronomical Telegrams.
| The KPNO International Spectroscopic Survey. III. [O III]-selected Survey List
The KPNO International Spectroscopic Survey (KISS) is an objective-prismsurvey for extragalactic emission-line objects. It combines many of thefeatures of previous slitless spectroscopic surveys with the advantagesof modern CCD detectors, and it is the first purely digitalobjective-prism survey for emission-line galaxies. Here we present thefirst list of emission-line galaxy candidates selected from our bluespectral data, which cover the wavelength range 4800-5500 Å. Inmost cases, the detected emission line is [O III] λ5007. Thecurrent survey list covers a 1°-wide strip located atδ=29°30' (B1950.0) and spanning the right ascension range8h30m to 17h0m. An area of116.6 deg2 is covered. A total of 223 candidate emission-lineobjects have been selected for inclusion in the survey list (1.91deg-2). We tabulate accurate coordinates and photometry foreach source, as well as estimates of the redshift, emission-line flux,and equivalent width based on measurements of the digitalobjective-prism spectra. The median apparent magnitude of the sample isB=18.2, and galaxies with redshifts approaching z=0.1 are detected. Theproperties of the KISS emission-line galaxies are examined using theavailable observational data and compared with previous surveys carriedout with photographic plates, as well as with the Hα-selectedportion of KISS.
| 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.
| 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 second KISO Survey for ultraviolet-excess galaxies. I
Not Available
| An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
| Large-Scale Structures in the Zone of Avoidance: The Galactic Anticenter Region
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJ...449..527L&db_key=AST
| KISO survey for ultraviolet-excess galaxies. XV
The fifteenth list and identification charts of the ultraviolet-excessgalaxies are presented. These galaxies were detected on the multicolorplates taken with the Kiso Schmidt telescope for 10 survey fields. Inthe sky area of 300 square degrees 544 objects are cataloged down to thephotographic magnitude of about 17.5.
| A Study of the Largescale Structure in the Distribution of Galaxies in a Region Centered about the Cancer Cluster - Part Two - Further Observational Results
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986AJ.....91..732B&db_key=AST
| The large-scale distribution of galaxies in the Linx-Gemini region
A redshift distribution study of a sample of 283 bright galaxies in an1800 square degree area in the Linx-Gemini region, including newredshifts for 59 galaxies, provides evidence for the existence ofseveral large scale structures. The Linx-Ursa supercluster with meanvelocity of 3500 km/s, a large cloud of galaxies extending for at least50/h Mpc around Abell 569, a low density filament in Gemini composedmainly of spirals, and a possible outstanding structure containing thecluster Abell 779, are found. The Abell 569 cloud is suggested as thestructure most likely connected with the Perseus supercluster across thegalactic dimming region.
| Analysis of groups of galaxies with accurate redshifts
Arecibo radio telescope redshift measurements have been obtained forover 100 galaxies in more than 40 different groups which generallyconsist of a large spiral galaxy with one or more companions. This setof data is supplemented with over 160 galaxies in more than 40 groupswhose dominant galaxy is brighter than 11.8 mag. An analysis of theentire sample indicates that typical structure in extragalactic space isone in which a large central galaxy has smaller and fainter companionsextending from about 20-900 kpc around. The companion galaxies in thesegroups have significantly higher redshifts than the brightest galaxy inthe group, confirming previous studies in whose results the companiongalaxies are systematically redshifted with respect to the dominantgalaxy.
| 21-cm observations of galaxies in groups and multiplets
Measures at the 21-cm line of neutral hydrogen are reported for a largesample of individual galaxies in groups as well as for interactingmultiple-component systems. The observations of single galaxies weredesigned to study differential redshifts within groups. Observations ofinteracting systems were undertaken to obtain system redshifts as wellas 21-cm profile morphology. The data, which will be used in futureanalyses, are presented here along with a discussion of interactionmorphology from the 21-cm profile point of view. Together the profilesamples encompass the full range of dynamical states in which the gascomponents of galaxies are observed, from relaxed to violentlydisrupted.
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