...stars

Based on observations made at the Observatoire de Haute Provence (CNRS), France, at the Jungfraujoch station of Observatoire de Genève, Switzerland, and on data from the ESA Hipparcos satellite.

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...stars

Tables 6 to 12 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

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...Z=0.018

This choice of a solar metallicity may appear surprising at first sight for Ap and Am stars, whose atmospheric composition is precisely far from solar. However, it is generally admitted that chemical peculiarities are confined to the superficial layers of the star (through radiative diffusion) so that the metal content integrated over the whole stellar mass is the same as for normal stars, and the deep internal structure remains roughly normal. But it is true that standard evolutionary tracks should be considered as a first approximation only for Ap and Am stars; they are also the only ones available as yet, though Michaud & Richer (1997) have recently computed fully consistent evolutionary tracks for F stars, including the effect of radiative diffusion on the internal stellar structure.

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...colours

Bonneau & Foy (1980) give $\Delta m = 1.5$ at 6500 Å, but the uncertainty seems too large for the inferred V-m₆₅₀₀ index to be really useful.

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...photometry

b-y = 0.220, m₁ = 0.225, c₁ = 0.656, V = 7.08.

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