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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.
| Supernova 2002bj in NGC 1821
IAUC 7844 available at Central Bureau for Astronomical Telegrams.
| Supernova 2002bj in NGC 1821
IAUC 7844 available at Central Bureau for Astronomical Telegrams.
| Supernova 2002bj in NGC 1821
IAUC 7839 available at Central Bureau for Astronomical Telegrams.
| 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.
| A volume-limited sample of IRAS galaxies to 4000 km/s, 3: CCD photometry from Palomar and Tololo observatories
An all-sky, quasi-volume-limited sample of 251 spiral galaxies within4000 km/s has been extracted from the redshift survey of InfraredAstronomy Satellite (IRAS) galaxies by Strauss (1992). Distance modulifor these objects estimated via the Tully-Fisher (TF) method allow thepeculiar velocity field and the cosmological density parameter to beconstrained within this volume. The TF relation we exploit relatesdeprojected neutral hydrogen line width to near-infrared luminosity.Herein we present I and V band photometry for 159 members of this sampleobtained with charge coupled device (CCD) cameras at Palomar and Tololoobservatories. Image processing and photometric calibration proceduresare described. Twenty seven objects with multiple calibratedobservations suggest that isophotal I band magnitudes are reproduced toequal to or less than 0.05 mag precision at sigmaI = 23.5 magarcsec-2, and that systematic run-to-run offsets are limitedto equal to or less than 0.05 I mag.
| A volume-limited sample of IRAS galaxies to 4000 km/s. I - Neutral hydrogen observations from Jodrell Bank
A volume-limited catalog is constructed of normal spiral galaxies withinthe redshift interval 0-4000 km/s and brighter than 1.9 Jy at 60 micronsto study relationships between fundamental galaxy properties and to mapto the peculiar velocity field. Observations of 57 galazies are reportedfrom this sample at Jodrell Bank, 42 of which resulted in detections,and study relationships between far-IR and neutral hydrogen properties.Gas and dynamical or halo mass are well correlated with each other andmoderately so with far IR luminosity. A decrease in dynamical mass withincreasing far-color temperature suggests that less massive, later-typesystems enjoy higher specific star-formation rates.
| Far infrared emission from galaxies
Until recently far infrared (FIR) observations of galaxies were limitedto about a dozen bright and/or active galaxies. New photometric data hasbecome available from Infrared Astronomical Satellite (IRAS) on 33galaxies (most of them faint). The FIR spectra of these galaxies aresimilar. The far infrared flux in the wavelength interval 9-118 micronsof the brighter galaxies is seen to be correlated with the integratedoptical magnitude. The 12 and 25 microns fluxes of these galaxiesexhibit the same dependence on the integrated optical magnitude as the10 and 21 microns fluxes for Seyferts and other emission-line galaxies.This suggests that the galaxies detected by IRAS are some type of activegalaxies in accord with the high percentage of these galaxies predictedby Lock and Rowan-Robinson (1983).
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