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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.
| The SCUBA Local Universe Galaxy Survey - III. Dust along the Hubble sequence
We present new results from the Submillimetre Common-User BolometerArray (SCUBA) Local Universe Galaxy Survey (SLUGS), the first largesystematic submillimetre (submm) survey of the local Universe. Since ourinitial survey of a sample of 104 IRAS-selected galaxies we have nowcompleted a survey of a sample of 81 optically selected galaxies,observed with the SCUBA camera on the James Clerk Maxwell Telescope.Since SCUBA is sensitive to the 90 per cent of dust too cold to radiatesignificantly in the IRAS bands our new sample represents the firstunbiased SCUBA survey of dust in galaxies along the whole length of theHubble sequence.We find little change in the properties of dust in galaxies along theHubble sequence, except a marginally significant trend for early-typegalaxies to be less-luminous submm sources than late types. Wenevertheless detected six out of 11 elliptical galaxies, although someof the emission may possibly be synchrotron rather than dust emission.As in our earlier work on IRAS galaxies we find that the IRAS and submmfluxes are well fitted by a two-component dust model with dustemissivity index β= 2. The major difference from our earlier workis that we find the ratio of the mass of cold dust to the mass of warmdust is much higher for our optically selected galaxies and can reachvalues of ~1000. Comparison of the results for the IRAS and opticallyselected samples shows that there is a population of galaxies containinga large proportion of cold dust that is unrepresented in the IRASsample.We derive local submm luminosity and dust mass functions, both directlyfrom our optically selected SLUGS sample, and by extrapolation from theIRAS Point Source Catalogue Redshift Survey (PSCz) survey using themethod of Serjeant and Harrison (by extrapolating the spectral energydistributions of the IRAS PSCz survey galaxies out to 850μm we probea wider range of luminosities than probed directly by the SLUGSsamples), and find excellent agreement between the two. We find them tobe well fitted by Schechter functions except at the highestluminosities. We find that as a consequence of the omission of coldgalaxies from the IRAS sample the luminosity function presented in ourearlier work is too low by a factor of 2, reducing the amount of cosmicevolution required between the low-z and high-z Universe.
| Supernovae 2005kg, 2005kh, 2005ki, 2005kj, 2005kk
IAUC 8632 available at Central Bureau for Astronomical Telegrams.
| Gas and Stars in an H I-Selected Galaxy Sample
We present the results of a J-band study of the H I-selected AreciboDual-Beam Survey and Arecibo Slice Survey galaxy samples using TwoMicron All Sky Survey data. We find that these galaxies span a widerange of stellar and gas properties. However, despite the diversitywithin the samples, we find a very tight correlation between luminosityand size in the J band, similar to that found in a previous paper byRosenberg & Schneider between the H I mass and size. We also findthat the correlation between the baryonic mass and the J-band diameteris even tighter than that between the baryonic mass and the rotationalvelocity.
| Supernova 2004bs in NGC 3323
IAUC 8344 available at Central Bureau for Astronomical Telegrams.
| Supernovae 2004bs and 2004bt
IAUC 8341 available at Central Bureau for Astronomical Telegrams.
| The Arecibo Dual-Beam Survey: Arecibo and VLA Observations
The Arecibo Dual-Beam Survey is a ``blind'' 21 cm search for galaxiescovering ~430 deg2 of sky. We present the data from thedetection survey as well as from the follow-up observations to confirmdetections and improve positions and flux measurements. We find 265galaxies, many of which are extremely low surface brightness. Some ofthese previously uncataloged galaxies lie within the zone of avoidance,where they are obscured by the gas and dust in our Galaxy. Eighty-one ofthese sources are not previously cataloged optically, and there are 11galaxies that have no associated optical counterpart or are onlytentatively associated with faint wisps of nebulosity on the DigitizedSky Survey images. We discuss the properties of the survey, and inparticular we make direct determinations of the completeness andreliability of the sample. The behavior of the completeness and itsdependencies is essential for determining the H I mass function. Weleave the discussion of the mass function for a later paper, but do notethat we find many low surface brightness galaxies and seven sources withMHI<108 Msolar. The AreciboObservatory is part of the National Astronomy and Ionosphere Center,which is operated by Cornell University under cooperative agreement withthe National Science Foundation. in Puerto Rico.
| 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 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.
| 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.
| 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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