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Galaxy coordinates. II. Accurate equatorial coordinates for 17298 galaxies
Using images of the Digitized Sky Survey we measured coodinates for17298 galaxies having poorly defined coordinates. As a control, wemeasured with the same method 1522 galaxies having accurate coordinates.The comparison with our own measurements shows that the accuracy of themethod is about 6 arcsec on each axis (RA and DEC).
| Chemical Evolution of the Galactic Disk: Evidence for a Gradient Perpendicular to the Galactic Plane
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995AJ....110.2813P&db_key=AST
| Global properties of dwarf galaxies II. Colours and luminosities
We have used a previously determined sample of 278 dwarf galaxies formost of which B magnitudes, optical colours, HI fluxes and IRASflux-densities are known, in order to derive luminosities, colours andsurface brightnesses. Dwarf galaxy properties are compared to those of acontrol sample of 228 larger spiral galaxies. The dwarf galaxies have onaverage higher 60/100μm flux ratios and lower 12/25μm flux ratiosthan the spiral galaxies, indicating that the contribution of `cirrus'to the infrared emission from dwarf galaxies is relativelyinsignificant. In the dwarf galaxies, the 60/100μm flux ratioincreases with increasing optical blueness; spiral galaxies show theopposite. Dwarf galaxies with a low optical surface brightness have low100μm/HI ratios, but the converse is not true. Galaxies with high100μm/HI ratios (indicative of high dust-to-gas ratios) also havehigh FIR/B ratios as well as high 60/100μm flux-density ratios.Although this is true for both spiral and dwarf galaxies, at given100μm/HI ratios the dwarf galaxies have both a lower FIR/B ratio anda higher 60/100μm flux-density ratio. This result is of importance inthe interpretation of FIR/B - 60/100μm diagrams in terms of starformation activity.
| Global properties of dwarf galaxies. I. Galaxy sample and IRAS infrared flux-densities
We have selected a sample of 278 dwarf galaxies for which at least Bmagnitudes and preferably also optical colour information are available.For those galaxies that have no previously published IRAS fluxes, wehave used the IRAS database to extract fluxes or upper limits tosensitivity levels significantly better than those of the IRAS PointSource Catalog. New IRAS data include 79 galaxies detected in at leastone band, and 66 galaxies with good upper limits. In total, about 60% ofall dwarf galaxies in the sample now have been detected at 60/100μm.
| H I observations of galaxies in between the Local and the Hydra/Centaurus superclusters
H I observations obtained with the 300-ft NRAO and 100-m Effelsbergradio telescopes in 1984-1985 are reported for 440 galaxies, ofmorphological types S0/a or later and diameter at least 2 arcmin in thecatalog of de Vaucouleurs et al., 1976, from the region between theLocal and Hya/Cen superclusters. The data are compiled in tables alongwith published data on 310 galaxies to form a data base for studies offilamentary structures in the intercluster region. More than 50 percentof the galaxies are detected in H I, and the redshift distribution isfound to be consistent with the existence of filaments.
| Integrated magnitudes and mean colors of DDO dwarf galaxies in the UBV system. II - Distances, luminosities, and H I properties
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1983AJ.....88..764D&db_key=AST
| Luminosity classifications of dwarf galaxies.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1966AJ.....71..922V&db_key=AST
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