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A new catalogue of ISM content of normal galaxies
We have compiled a catalogue of the gas content for a sample of 1916galaxies, considered to be a fair representation of ``normality''. Thedefinition of a ``normal'' galaxy adopted in this work implies that wehave purposely excluded from the catalogue galaxies having distortedmorphology (such as interaction bridges, tails or lopsidedness) and/orany signature of peculiar kinematics (such as polar rings,counterrotating disks or other decoupled components). In contrast, wehave included systems hosting active galactic nuclei (AGN) in thecatalogue. This catalogue revises previous compendia on the ISM contentof galaxies published by \citet{bregman} and \citet{casoli}, andcompiles data available in the literature from several small samples ofgalaxies. Masses for warm dust, atomic and molecular gas, as well asX-ray luminosities have been converted to a uniform distance scale takenfrom the Catalogue of Principal Galaxies (PGC). We have used twodifferent normalization factors to explore the variation of the gascontent along the Hubble sequence: the blue luminosity (LB)and the square of linear diameter (D225). Ourcatalogue significantly improves the statistics of previous referencecatalogues and can be used in future studies to define a template ISMcontent for ``normal'' galaxies along the Hubble sequence. The cataloguecan be accessed on-line and is also available at the Centre desDonnées Stellaires (CDS).The catalogue is available in electronic form athttp://dipastro.pd.astro.it/galletta/ismcat and at the CDS via anonymousftp to\ cdsarc.u-strasbg.fr (130.79.128.5) or via\http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/405/5
| The Southern Sky Redshift Survey
We report redshifts, magnitudes, and morphological classifications for5369 galaxies with m_B <= 15.5 and for 57 galaxies fainter than thislimit, in two regions covering a total of 1.70 sr in the southerncelestial hemisphere. The galaxy catalog is drawn primarily from thelist of nonstellar objects identified in the Hubble Space TelescopeGuide Star Catalog (GSC). The galaxies have positions accurate to ~1"and magnitudes with an rms scatter of ~0.3 mag. We compute magnitudes(m_SSRS2) from the relation between instrumental GSC magnitudes and thephotometry by Lauberts & Valentijn. From a comparison with CCDphotometry, we find that our system is homogeneous across the sky andcorresponds to magnitudes measured at the isophotal level ~26 magarcsec^-2. The precision of the radial velocities is ~40 km s^-1, andthe redshift survey is more than 99% complete to the m_SSRS2 = 15.5 maglimit. This sample is in the direction opposite that of the CfA2; incombination the two surveys provide an important database for studies ofthe properties of galaxies and their large-scale distribution in thenearby universe. Based on observations obtained at Cerro TololoInter-American Observatory, National Optical Astronomy Observatories,operated by the Association of Universities for Research in Astronomy,Inc., under cooperative agreement with the National Science Foundation;Complejo Astronomico El Leoncito, operated under agreement between theConsejo Nacional de Investigaciones Científicas de laRepública Argentina and the National Universities of La Plata,Córdoba, and San Juan; the European Southern Observatory, LaSilla, Chile, partially under the bilateral ESO-ObservatórioNacional agreement; Fred Lawrence Whipple Observatory;Laboratório Nacional de Astrofísica, Brazil; and the SouthAfrican Astronomical Observatory.
| Scaleheights of 486 southern spiral galaxies and some statistical correlation
Based on Peng's method (1988), we obtain scaleheights of 486 southernspiral galaxies, the images of which are taken from the Digitized SkySurvey at Xinglong Station of Beijing Astronomical Observatory. Thefitted spiral arms of 70 galaxies are compared with their images to gettheir optimum inclinations. The scaleheights of other 416 ones arelisted in Table A1 in Appendix. After compiling and analyzing the data,we find some statistical correlations. The most interesting results arethat a flatter galaxy is bluer and looks brighter, and galaxies becomeflatter along the Hubble sequence Sab -- Scd. Based on photographic dataof the National Geographic Society -- Palomar Observatory Sky Survey(NGS-POSS) obtained using the Oschin Telescope Palomar Mountain. TheNGS-POSS was funded by a grant from the National Geographic Society tothe California Institute of Technology. The plates were processed intothe present compressed digital form with their permission. The DigitizedSky Survey was produced at the Space Telescope Science Institute underUS Government grant NAG W-2166. Table A1 is available in electronic fromonly, via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstract.html
| 1.25-mm observations of a complete sample of IRAS galaxies. II. Dust properties.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996MNRAS.283...85A&db_key=AST
| CO, HI and cold dust in a sample of IRAS galaxies.
Using the IRAM 30m, SEST 15m, and Nancay radiotelescopes, we havegathered the 1mm continuum emission, the intensities of the J=1-0 lineof the CO molecule and of the atomic hydrogen line at 21cm for twosamples of IRAS galaxies. The southern sample was selected from the IRASCatalogue and is complete at the limiting flux of 2Jy at 60μm; of the10 northern objects 7 belong to the Smith et al. complete sample (1987)and 3 are isolated objects. Using these data, we have estimated theatomic hydrogen masses from the 21cm emission, the molecular gas massesfrom the CO(1-0)line brightness, and the dust and gas masses from the mmcontinuum emission using two "extreme" dust models. The main conclusionsof this work for far-infrared selected galaxies can be summarized in thefollowing points: (1) the median value of M_H_2__/M_HI_ is 0.5, meaningthat the atomic phase dominates in these galaxies. The fraction of gasin molecular form increases with increasing FIR luminosity but does notshow any obvious trend with other galaxy properties, in particular withthe FIR surface brightness. (2) the H_2_ surface density derived fromCO(1-0)emission is better correlated with the cold dust surface densitythan the HI surface density, but the correlation of HI with dust is notnegligible (we found a correlation coefficient of 0.5, while thecorrelation coefficient with σ_H_2__ is 0.70). Thus, globally inthese galaxies, the cold dust emission is likely associated with boththe molecular and atomic phases. Indeed, the dust surface density isalso correlated with the total gas surface density. (3) the FIR surfacebrightness increases as the third power of the S(60μm) /S(100μm)ratio. It shows a tight correlation with both the H_2_ and dust surfacedensities and a weaker one with the HI surface density. This suggeststhat a large part of the far-infrared emission of these galaxiesoriginates in the molecular medium. (4) the gas-to-dust ratio, (M_H_2__+M_HI_)/M_d_ ranges between 100 and 1000 and its average value is 230,close to the Galactic value. There is indeed a clear trend: this ratiodecreases as the FIR surface density increases. This result can beexplained in the framework of an enhancement of metallicity in galaxydiscs having a higher star formation rate.
| The extended 12 micron galaxy sample
We have selected an all-sky (absolute value of b greater than or equalto 25 deg) 12 micron flux-limited sample of 893 galaxies from the IRASFaint Source Catalog, Version 2 (FSC-2). We have obtained accurate totalfluxes in the IRAS wavebands by using the ADDSCAN procedure for allobjects with FSC-2 12 micron fluxes greater than 0.15 Jy and increasingflux densities from 12 to 60 microns, and defined the sample by imposinga survey limit of 0.22 Jy on the total 12 micron flux. Its completenessis verified, by means of the classical log N - log S andV/Vmax tests, down to 0.30 Jy, below which we have measuredthe incompleteness down to the survey limit, using the log N - log Splot, for our statistical analysis. We have obtained redshifts (mostlyfrom catalogs) for virtually all (98.4%) the galaxies in the sample.Using existing catalogs of active galaxies, we defined a subsample of118 objects consisting of 53 Seyfert 1s and quasars, 63 Seyfert 2s, andtwo blazars (approximately 13% of the full sample), which is the largestunbiased sample of Seyfert galaxies ever assembled. Since the 12 micronflux has been shown to be about one-fifth of the bolometric flux forSeyfert galaxies and quasars, the subsample of Seyferts (includingquasars and blazars) is complete not only to 0.30 Jy at 12 microns butalso with respect to a bolometric flux limit of approximately 2.0 x10-10 ergs/s/sq cm. The average value of V/Vmaxfor the full sample, corrected for incompleteness at low fluxes, is 0.51+/- 0.04, expected for a complete sample of uniformly distributedgalaxies, while the value for the Seyfert galaxy subsample is 0.46 +/-0.10. We have derived 12 microns and far-infrared luminosity functionsfor the AGNs, as well as for the entire sample. We extracted from oursample a complete subsample of 235 galaxies flux-limited (8.3 Jy) at 60microns. The 60 micron luminosity function computed for this subsampleis in satisfactory agreement with the ones derived from the brightgalaxy sample (BGS) and the deep high-galactic latitude sample, bothselected at 60 microns.
| The relationship between the radio and far-infrared emission in IRAS galaxies - VLA observations of a large well-defined sample at 1420 MHz
An examination of VLA observations at 1420 MHz of a well-defined sampleof 156 IRAS galaxies reveals a strong correlation between the radio andfar-infrared emission from IRAS galaxies. The flux density ratio isfound to have a constant value of -4.82. The results suggest that thenonthermal radio emission is closely related to the current level ofstar formation, and that the star formation region in most IRAS galaxiesis confined to the central few kpc of the galaxy.
| The Identification of IRAS Point Sources - Part One - a 304-DEGREE Field Centred on the South Galactic Pole
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986MNRAS.223..279W&db_key=AST
| Southern Galaxy Catalogue.
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