Bibcode
Arribas, S.; Martinez Roger, C.
Referencia bibliográfica
Astronomy and Astrophysics (ISSN 0004-6361), vol. 206, no. 1, Nov. 1988, p. 63-73.
Fecha de publicación:
11
1988
Número de citas
35
Número de citas referidas
32
Descripción
A new empirical calibration of the (B-V) index versus the three
fundamental stellar parameters T(eff), (Fe/H), and log g is presented
whose range of validity is adequate to analyze the main sequence and
turnoff regions of most of the stellar cluster systems. Significant
systematic differences are found between this new calibration and
previous ones based on model atmosphere predictions. On the one hand,
solar abundance models are systematically too blue for T(eff) between
8000 K and 6500 K and too red for T(eff) between 6500 K and 5000 K. On
the other hand, it appears that current atmospheric models are
underestimating the variation of the (B-V) color due to metallicity.
When the new calibration is used to compare recent high-quality
color-magnitude diagrams with the revised VandenBerg isochrones, very
good agreement is found for the metal-rich or moderately poor clusters,
but discrepancies are found for the most metal-poor clusters.