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Pulkovo compilation of radial velocities for 35495 stars in a common system.
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| Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.
| Speckle Observations of Binary Stars with the WIYN Telescope. III. A Partial Survey of A, F, and G Dwarfs
Two hundred thirty nearby main-sequence stars with spectral types in therange of A to G have been observed by way of speckle interferometryusing the WIYN 3.5 m telescope at Kitt Peak, Arizona. The stars had noprevious mention of duplicity in the literature. Of those observed, 14showed clear evidence of a companion, and 63 were classified assuspected nonsingle based on a power spectrum analysis. The remainingstars discussed show no evidence of duplicity to the limit of thedetection system in high-quality observations. The WIYN Observatory is ajoint facility of the University of Wisconsin-Madison, IndianaUniversity, Yale University, and the National Optical AstronomyObservatory.
| Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
| UBV photometry of stars whose positions are accurately known.
Photometric indices V, B-V, and U-B were measured for about 560 stars ofthe AGK3R and NPZT catalogs between BD declinations 11 deg and 23 deg,using the 40-cm Cassegrain telescope of the Kvistaberg Observatory fromApril 1986 to May 1987. The observation procedure and the reductiontechnique were the same as in the earlier papers of this series by Oja(1984, 1985, 1986, and 1987). The mean errors were calculated from theinternal consistency of the data. The accuracy was found to be the sameas for the earlier parts of the survey.
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| Takýmyýldýz: | Buyuk Ayi |
| Sað Açýklýk: | 10h07m45.05s |
| Yükselim: | +45°08'14.9" |
| Görünürdeki Parlaklýk: | 8.294 |
| Uzaklýk: | 158.983 parsek |
| özdevim Sað Açýklýk: | -13.6 |
| özdevim Yükselim: | 16 |
| B-T magnitude: | 8.614 |
| V-T magnitude: | 8.321 |
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