Tracks of the same models as those shown in Fig. 1, in the sHR diagram. While the ordinate is defined via the spectroscopically measurable quantities T_eff and log g, its numerical value gives the logarithm of the luminosity-to-mass ratio, in solar units. The right-side ordinate scale gives the atmospheric Eddington factor for hot hydrogen-rich stars. The horizontal line at log L/ L_⊙ ≃ 4.6 indicates the location of the Eddington limit. The dotted straight lines are lines of constant log g, as indicated.