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HD 21949


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DDO spectroscopic survey of MOST variable stars
A spectroscopic support survey of 103 objects observed by theMicrovariability and Oscillations of STars (MOST) satellite ispresented; 96 are variable stars with 83 of them being new MOSTvariable-star detections or stars with variability types verified and/ormodified on the basis of the MOST data. The analysis of 241medium-resolution spectra using the broadening-function formalismyielded radial velocities, projected rotational velocities (for 31targets for which it was possible) and spectral-type estimates. Sevennew spectroscopic binaries were discovered; orbital solutions are givenfor two of them (HD 73709 and GSC 0814-0323). The visual binary HD 46180was found to be composed of two close binary stars (eclipsing andnon-eclipsing one), very probably forming a physical quadruple system.Based on spectroscopic data from the David Dunlap Observatory (DDO),University of Toronto.E-mail: pribulla@ta3.sk

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.

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Dades d'Observació i Astrometria

Constel·lació:Eridanus
Ascensió Recta:03h32m02.44s
Declinació:-08°48'39.6"
Magnitud Aparent:9.222
Moviment propi RA:-0.7
Moviment propi Dec:9.7
B-T magnitude:9.739
V-T magnitude:9.265

Catàlegs i designacions:
Noms Propis   (Edit)
HD 1989HD 21949
TYCHO-2 2000TYC 5296-283-1
USNO-A2.0USNO-A2 0750-00782578
HIPHIP 16462

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