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Two Boehm-Vitense gaps in the main sequence of the Hyades

Jos H. J. de Bruijne·Ronnie Hoogerwerf·P. Tim de Zeeuw
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Abstract

Hipparcos proper motions and trigonometric parallaxes allow the derivation of secular parallaxes which fix the distances to individual stars in the Hyades cluster to an accuracy of \sim 2 percent. The resulting color-absolute magnitude diagram for 92 high-fidelity single members of the cluster displays a very narrow main sequence, with two turn-offs and associated gaps. These occur at the locations where the onset of surface convection affects the B-V colors, as predicted by Boehm-Vitense thirty years ago. The new distances provide stringent constraints on the transformations of colors and absolute magnitudes to effective temperatures and luminosities, and on models of stellar interiors.

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Jos H. J. de Bruijne, Ronnie Hoogerwerf, P. Tim de Zeeuw. 2000-11-08. Two Boehm-Vitense gaps in the main sequence of the Hyades. https://doi.org/10.1086/317296

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