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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.
| Walraven photometry of nearby southern OB associations
Homogeneous Walraven (VBLUW) photometry is presented for 5260 stars inthe regions of five nearby southern OB associations: Scorpio Centaurus(Sco OB2), Orion OB1, Canis Major OB1, Monoceros OB1, and Scutum OB2.Derived V and (B - V) in the Johnson system are included.
| Radial velocities from microdensitometer scans of objective-prism spectra
Measures were made from scans of objective-prism spectra of more than1000 stars on four plates using a PDS microdensitometer. The plates areall of a single star field and were taken with the CTIO Schmidttelescope. They have been measured by hand in the course of theobjective-prism radial velocity survey of CIDA. Reductions of themeasures were made in order to determine whether this very rapid machinecan be used to obtain positions of spectral lines with no loss ofprecision when compared to the measures made by hand. Results of thereduction show that the PDS measures can be used to obtain radialvelocities as accurately as the hand measures. In addition, photometricparameters are computed which allow the determination of photographicblue magnitudes, color indices, and quantitative spectralclassifications. The ease and rapidity of obtaining the scans indicatethat many large-scale studies of galactic structure and kinematics arepractical as well as possible.
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
| Csillagkép: | Kentaur |
| Rektaszcenzió: | 14h13m23.94s |
| Deklináció: | -33°31'05.8" |
| Vizuális fényesség: | 7.832 |
| Távolság: | 167.504 parszek |
| RA sajátmozgás: | -22.1 |
| Dec sajátmozgás: | -24.1 |
| B-T magnitude: | 8.212 |
| V-T magnitude: | 7.864 |
Katalógusok és elnevezések:
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