Thermal and chemical profiles at the crossing of the dynamical curves. The line types used for the models from Table 1 are the same as those used in Fig. 2. Top panel: temperature profiles. From top to bottom (at M ~ 0.2 M_⊙) the curves belong to models CF88, LER-1.5-0.001-1.0, LER-1.7-0.1-1.0, LER-1.5-0.1-1.0, LER-1.3-0.1-1.0, and LER-1.5-10.-1.0. Note that the last two models run away off-center. Bottom panel: ¹²C mass fraction profiles. For comparison purposes, we have plotted with a thin solid line the profile of model CF88 at the crossing of the ignition curve. As can be easily appreciated, the extension of the convective core is very sensitive to the inclusion of a LER in the ¹²C+¹²C reaction rate.