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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.
| A proper motion study of the globular cluster M 10
We present the first proper motion study of M 10 (NGC 6254). Absoluteproper motions of about 532 stars in the field of the globular cluster M10 were determined with respect to Hipparcos and ACT reference stars. Inaddition to photographic plates of Bonn and Shanghai also wide field CCDobservations as second epoch plates were used. The wide field CCDobservations show an accuracy comparable to that of the photographicplates. A good coincidence of the solutions based on reference starsfrom Hipparcos and from ACT was found. Our final proper motions allow asufficient separation of cluster and field stars. Two population IICepheids were confirmed to be members of M 10. The absolute propermotion of M 10 was determined and combined with its distance from theSun and its radial velocity. The space motion and metallicity of M 10indicates the characteristics of a halo object with an orbit reaching toa maximal z-distance of less than 3 kpc.
| Early type high-velocity stars in the solar neighborhood. IV - Four-color and H-beta photometry
Results are presented from photometric obaservations in the Stromgrenuvby four-color and H-beta systems of early-type high-velocity stars inthe solar neighborhood. Several types of photometrically peculiar starsare selected on the basis of their Stromgren indices and areprovisionally identified as peculiar A stars, field horizontal-branchstars, metal-poor stars near the Population II and old-disk turnoffs,metal-poor blue stragglers, or metallic-line A stars. Numerousphotometrically normal stars were also found.
| The interstellar reddening in front of globular clusters.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975PASP...87...65C&db_key=AST
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