Lithium depletion in the Sun: A study of mixing based on hydrodynamical simulations

Based on radiation hydrodynamics modeling of stellar convection zones, a di ffusion scheme has been devised describing the downward penetration of conv ective motions beyond the Schwarzschild boundary (overshoot) into the radia tive interior. This scheme of exponential diffusive overshoot has already b een successfully applied to AGE stars. Here we present an application to th e Sun in order to determine the time scale and depth extent of this additio nal mixing, i.e. diffusive overshoot at the base of the convective envelope . We calculated the associated destruction of lithium during the evolution towards and on the main-sequence. We found that the slow-mixing processes i nduced by the diffusive overshoot may lead to a substantial depletion of li thium during the Sun's main-sequence evolution.