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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 catalog of K giants at the South Galactic Pole - Broadband and DDO photometry and radial velocities
We describe a sample of K giants at the South Galactic Pole, selected toexamine the chemical and kinematical properties of stars perpendicularto the galactic plane and to measure the local column density of thedisk. We report velocities, abundances, absolute magnitudes, andbroadband BV photometry for over 500 giants.
| Local dark matter from a carefully selected sample
The precise data obtained by Flynn and Freeman (1991) on K giants at thesouth Galactic pole are used to analyze the amount of local dark matterin which the systematic effects can be modeled easily and evaluatedaccurately. The method of Bahcall (1984) is employed to solve theself-consistent equations for the distribution of dark matter. TheK-giant survey is found to provide significant evidence for disk darkmatter. Taking into account all recognized sources of error using astatistical test devised by Gould (1989, 1990), a model with no darkmatter is inconsistent with the data at the 86-percent confidence level.The best-fit P-model (in which dark matter is distributed proportionallyto known matter) has 53 percent more dark matter than visible matter.
| Multiplicity among solar-type stars
The paper presents results of a search for spectroscopic binaries among135 bright field stars of types F3 - G2 IV or V. Orbital elements for 25newly discovered spectroscopic binaries are derived from radialvelocities measured in 20 coude spectra for each star, and velocitycurves are also computed for each of these binaries. It is found thatthe ratios of observed singles:doubles:triples:quadruples among the 135program stars are 42:46:9:2. The 88 computed and estimated periods showa relatively smooth distribution with a single maximum and a medianperiod of 14 years. It is tentatively suggested that the discoveredbinaries show no pronounced grouping tendency in age or evolutionarystate. The number of binaries not revealed is estimated, the secondarymasses for both the observed and undetected binaries are determinedstatistically, and it is concluded that the short-period binaries arefission systems while the long-period systems are those in which pairsof protostars contracted separately. On the average, the multiplesystems are found to be 0.22 magnitude brighter than the primariesalone.
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