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SANTIAGO 91, a right ascension catalogue of 3387 stars (equinox J2000). The positions in right ascension of 3387 stars belonging to the Santiago67 Catalogue, observed with the Repsold Meridian Circle at Cerro Calan,National Astronomical Observatory, during the period 1989 to 1994, aregiven. The average mean square error of a position, for the wholeCatalogue, is +/-0.009 s. The mean epoch of the catalogue is 1991.84.
| A kinematic and abundance survey at the galactic poles The DDO intermediate band system is used to obtain detailed informationabout abundance gradients and velocity dispersions in the galaxy, withan emphasis on the properties of halo stars in the range of from 1 to 5kpc. The DDO abundance index is calibrated agianst (Fe/H) for metal-poorstars, with a resulting gradient of about -0.2 per kpc. However, whenthe sample is divided into two subsamples with (Fe/H) less than -0.5 andequal to or greater than -0.5, the gradients are -0.14 and 0.00,respectively. DDO observations of about 1000 stars, mostly G5-K5 giants,show that the velocity dispersion increases both with decrease inmetallicity and increase in z distance. The abundances found for high-zstars are similar to the A-star results of Rodgers (1971) in that abouthalf the K giants above 1 kpc appear to have solar abundances.
| The K-giant population at the South Galactic Pole CN anomalies and distances from the galactic plane have been derivedthrough DDO photometry for 171 late-type giant and subgiant stars nearthe South Galactic Pole. The previously found trend of the difference inCN concentration with distance (approximately equal to 0.09/kpc) holdsto approximately 2 kpc, but at greater distances from the plane theslope becomes approximately zero. The giants beyond 2 kpc are ofessentially normal composition or only slightly underabundant in heavierelements.
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Takýmyýldýz: | Yontar |
Sað Açýklýk: | 00h30m38.13s |
Yükselim: | -28°32'10.7" |
Görünürdeki Parlaklýk: | 9.053 |
özdevim Sað Açýklýk: | 11.9 |
özdevim Yükselim: | -17 |
B-T magnitude: | 10.307 |
V-T magnitude: | 9.157 |
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