Classification of Population II Stars in the Vilnius Photometric System. I. Methods
The methods used for classification of Population II stars in theVilnius photometric system are described. An extensive set of standardswith known astrophysical parameters compiled from the literature sourcesis given. These standard stars are classified in the Vilnius photometricsystem using the methods described. The accuracy of classification isevaluated by a comparison of the astrophysical parameters derived fromthe Vilnius photometric system with those estimated from spectroscopicstudies as well as from photometric data in other systems. For dwarfsand subdwarfs, we find a satisfactory agreement between our reddeningsand those estimated in the uvbyscriptstyle beta system. The standarddeviation of [Fe/H] deter mined in the Vilnius system is about 0.2 dex.The absolute magnitude for dwarfs and subdwarfs is estimated with anaccuracy of scriptstyle <=0.5 mag.
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Three-dimensional calssification of F-M type halo stars in the Vilnius photometric system
Not Available
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Observations of carbon monoxide in metal-deficient stars
A sample of cool metal-deficient giant stars has been observed to obtainan estimate of the CO abundance independent of metallicity. The strengthof the 2.3-micron first-overtone carbon monoxide band was measuredphotometrically using intermediate-bandwidth filters. For late-typegiants with Fe/H from about zero to -1.5 the CO index decreases withdecreasing metallicity from the mean relation for Population I giants.Stars more metal-poor than Fe/H = -1.5 show uniformly weak orundetectable CO. Among giant stars of intermediate metallicity, thescatter in the observed CO strength as a function of Fe/H may be largerthan can be attributed to observational error. A range in the abundanceratio CNO/Fe in metal-poor field giants is suggested.
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Light and radial velocity observations of classical Cepheids
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...32..399E&db_key=AST
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A Search for Metal-Deficient Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970ApJS...22..117B&db_key=AST
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