Stellar diameters and temperatures. III. Main-sequence A, F, G, and K stars: additional high-precision measurements and empirical relations

TS Boyajian, K Von Braun, G Van Belle… - The Astrophysical …, 2013 - iopscience.iop.org
The Astrophysical Journal, 2013iopscience.iop.org
Based on CHARA Array measurements, we present the angular diameters of 23 nearby,
main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host
stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars
using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined
with previously published values to create an Angular Diameter Anthology of measured
angular diameters to main-sequence stars (luminosity classes V and IV). This compilation …
Abstract
Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color–temperature relations to an assortment of color indices in the Johnson (BVR J I J JHK), Cousins (R C I C), Kron (R K I K), Sloan (griz), and WISE (W 3 W 4) photometric systems. These relations have an average standard deviation of∼ 3% and are valid for stars with spectral types A0–M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T eff> 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only∼ 2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.
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