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 2004I in NGC 1072
IAUC 8275 available at Central Bureau for Astronomical Telegrams.
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Supernovae 2004H, 2004I, and 2004J
IAUC 8272 available at Central Bureau for Astronomical Telegrams.
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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.
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A Study of External Galaxies Detected by the COBE Diffuse Infrared Background Experiment
A comparison of the COBE 1 Diffuse Infrared Background Experiment(DIRBE) all-sky survey with the locations of known galaxies in the IRASCatalog of Extragalactic Objects and the Center for Astrophysics Catalogof Galaxies led to the detection of as many as 57 galaxies. In thispaper, we present the photometric data for these galaxies and ananalysis of the seven galaxies that were detected at lambda > 100 mum. Estimates of the ratio of the mass of the cold dust (CD) componentdetected at Td = 20-30 K to a very cold dust (VCD) component with Td ~10-15 K suggest that between 2%-100% of the cirrus-like CD mass can alsoexist in many of these galaxies as VCD. In one galaxy, M33, the DIRBEphotometry at 240 mu m suggests as much as 26 times as much VCD may bepresent as compared to the cirrus-like component. Further submillimetermeasurements of this galaxy are required to verify such a largepopulation of VCD. We also present 10 galaxies that were detected in thesky region not previously surveyed by IRAS and that can be used toconstruct a flux-limited all-sky catalog of galaxies brighter than 1000Jy with a modest completeness limit of about 65%.
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KISO survey for ultraviolet-excess galaxies. XVII
Presented here are the 17th list and identification charts of theUV-excess galaxies which have been detected on the multicolor platestaken with the Kiso Schmidt telescope for 10 survey fields. In the skyarea of some 300 sq deg 379 objects are catalogued down to aphotographic magnitude of about 18.
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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.
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Low-frequency radio continuum evidence for cool ionized gas in normal spiral galaxies
A 57.5-MHz survey of a total of 133 (mostly late-type spiral) galaxieshas resulted in the detection of 68. The ratio of observed intensitiesto intensities extrapolated from higher-frequency measurements is wellcorrelated with the axial ratio of the observed galaxies, and isinterpretable due to increasing free-free absorption of nonthermalemission in galaxy disks with increasing tilt. The implied free-freeabsorption is interpreted as due to the pervasive presence of a clumpymedium of well-mixed, nonthermally emitting, thermally absorbing gaswith small filling factor.
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A survey of galaxy redshifts. IV - The data
The complete list of the best available radial velocities for the 2401galaxies in the merged Zwicky-Nilson catalog brighter than 14.5mz and with b (II) above +40 deg or below -30 deg ispresented. Almost 60 percent of the redshifts are from the CfA surveyand are accurate to typically 35 km/s.
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