Evolutionary tracks for models in the range 0.10--1.25 Msun, with various values of the mixing length parameter alpha_MLT = 0.5, 1.0, 1.875, 3.0,and various chemical composition ([Fe/H] = +0.3, 0.0, -0.5, -1.0, -1.5, enrichment parameter Delta Y /Delta Z = 1.48, alpha-enhancement [alpha/Fe] = 0; the Grevesse & Sauval 1998 ((Z/X)_sun = 0.0230 is assumed) are available. Diffusion of helium and of the heavy elements is taken into account; core overshooting is ignored. The evolutionary tracks cover the PMS and the post-MS up to 13 Gyr and/or the sub giant phase (if present). Along with the standard input physics incorporated in the non-rotational version of YREC (Demarque et al., 2008), these new calculations feature two major improvements which are especially relevant to models of mass lower than 0.6 Msun:

(1) to take care of the (relatively) low temperatures and high densities in the atmospheres of such stars, the SCVH equation of state (Saumon et al. 1995) is ramped with the OPAL 2005 equation of state below 5000 K;

(2) as the grey atmosphere approximation becomes increasingly inadequate at about 0.6 Msun and moving towards lower masses, the surface boundary conditions have been specified based on the BT-Settl PHOENIX non-grey atmospheric models (Allard et al., 2011).

Theoretical isochrones, along with synthetic magnitudes obtained from the color--effective temperature transformations of Lejeune et al. (1998) and VandenBerg & Clem (2003), are also available.