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UBV photometry of HD stars in the fields of selected cataclysmic variables.
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Intermediate band, RI, and DDO photometry of the weak-lined stars in thefirst three volumes of the Michigan catalogs of spectral type arediscussed on the basis of luminosity and heavy element abundance. Theinterface between the old disk (Fe/H greater than -0.8 dex) and halo(Fe/H less than -1.2 dex) populations represents discontinuities in boththe stellar motions and the stellar physics. The CN strengths of bothevolved and unevolved halo stars decrease with decreasing temperature,in a mirror image of the increase with decreasing temperature for thedisk objects. The result for the halo giants has been attributed to deepmixing in the stellar atmospheres but the similar result for unevolveddwarfs indicates a difference in formation rather than in evolutionaryprocess of the two populations.
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| Catalogue of Metal-Deficient F-Stars to M-Stars - Part One - Stars Classified Spectroscopically - Supplement One
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Osservazione e dati astrometrici
| Costellazione: | Sagittario |
| Ascensione retta: | 19h52m07.17s |
| Declinazione: | -41°55'00.1" |
| Magnitudine apparente: | 9.697 |
| Moto proprio RA: | -4.7 |
| Moto proprio Dec: | 15.4 |
| B-T magnitude: | 10.3 |
| V-T magnitude: | 9.747 |
Cataloghi e designazioni:
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