Classification and properties of UV extinction curves
The catalog of Savage et al. (\cite{ref27}) reporting colour excesses of1415 stars from ANS photometry offers the opportunity to deeplyinvestigate the characteristics of UV extinction curves which differfrom the standard extinction of the diffuse interstellar medium. To thisaim we have selected a sample of 252 curves, which have been comparedwith the relations derived by Cardelli et al. (\cite{ref4}; CCM in thefollowing) for a variety of R_V values in the range 2.4-5 and have beenclassified as normal if they fit at least one of the CCM curves oranomalous otherwise. We find that normal curves with small R_V are justas numerous as those with large R_V. The anomalous objects are arrangedinto two groups according to the strength of the bump at 0.217 mu . Fora given value of c_2 this increases along the sequence: type Aanomalous, normals and type B anomalous, suggesting that this sequenceshould correspond to an increase of the amount of small grains along thesightline. Considerations concerning the environmental characteristicsindicate that the anomalous behaviour is not necessarily tied to theexistence of dense gas clouds along the line of sight.
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UBV beta Database for Case-Hamburg Northern and Southern Luminous Stars
A database of photoelectric UBV beta photometry for stars listed in theCase-Hamburg northern and southern Milky Way luminous stars surveys hasbeen compiled from the original research literature. Consisting of over16,000 observations of some 7300 stars from over 500 sources, thisdatabase constitutes the most complete compilation of such photometryavailable for intrinsically luminous stars around the Galactic plane.Over 5000 stars listed in the Case-Hamburg surveys still lackfundamental photometric data.
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A spectroscopic database for Stephenson-Sanduleak Southern Luminous Stars
A database of published spectral classifications for objects in theStepenson-Sanduleak Luminous Stars in the Southern Milky Way catalog hasbeen compiled from the literature. A total of 6182 classifications for2562 stars from 139 sources are incorporated.
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The List of the Pairs of Stars with Different Light Absorptions in the Circumstellar Environments
Not Available
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Eight-colour photometry of stars associated with selected Sharpless H II regions at L exp II of about 190 deg - S 252, S 254, S 255, S 257, and S 261
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1987A&A...171..216C&db_key=AST
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The interstellar 217 NM band - A third catalogue of equivalent widths
A catalog of equivalent widths of the 217 nm interstellar absorptionband as well as other parameters characterizing the extinction curve inthe ultraviolet has been compiled for 790 O and B stars. A relativelytight correlation between the equivalent width of the 217 nm band andE(B-V) indicates that the absorber of this band is connected with thepopulation of larger interstellar grains responsible for the visualextinction. The parameter characterizing the amount of extinction in thefar UV is only weakly correlated with E(B-V), a result in accord withthe assumption that a second population of very small grains causes therapid increase of the far-UV extinction.
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A catalog of ultraviolet interstellar extinction excesses for 1415 stars
Ultraviolet interstellar extinction excesses are presented for 1415stars with spectral types B7 and earlier. The excesses with respect to Vare derived from Astronomical Netherlands Satellite (ANS) 5-channel UVphotometry at central wavelengths of approximately 1550, 1800, 2500, and3300 A. A measure of the excess extinction in the 2200-A extinction bumpis also given. The data are valuable for investigating the systematicsof peculiar interstellar extinction and for studying the character of UVinterstellar extinction in the general direction of stars for which theextinction-curve shape is unknown.
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Exciting stars and the distances of the diffuse nebulae
Not Available
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The rotation and structure of the galaxy beyond the solar circle. I - Photometry and spectroscopy of 276 stars in 45 H II regions and other young stellar groups toward the galactic anticentre
Abstract image available at:http://adsabs.harvard.edu/abs/1979A&AS...38..197M
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Study of a triple emission nebula in Orion
The H II regions S254, 255, and 257 in the constellation Orion are closetogether on the sky and appear like a triple object. Fabry-Perot radialvelocities of the H II regions as well as UBV photoelectric magnitudesof their exciting stars are obtained. The data show that (1) all threenebulae are at a distance of 2.5 kpc; (2) an excess extinction isobserved in S255 and S257 while S254 shows no excess extinction; and (3)S255, identified as an IR and a molecular source, is the youngest objectof the group. It is concluded that the three H II regions are atdifferent evolutionary stages.
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Interaction of hot stars and of the interstellar medium. III. Excitation sources for small galactic nebulae.
Abstract image available at:http://adsabs.harvard.edu/abs/1973A&A....29..225C
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Observations de nouvelles regions HII galactiques et d'etoiles excitatrices
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....25..337G&db_key=AST
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Vitesses radiales et distances des regions HII galactiques.
Not Available
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Radial Velocities and Kinematics of Galactic H II Regions
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1968ApJ...151..473M&db_key=AST
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Symmetric Galactic Nebulae.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJ...121..604J&db_key=AST
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