EAS Publications Series

Stellar Evolution and Seismic Tools for Asteroseismology - Diffusive Processes in Stars and Seismic Analysis
C.W. Straka, Y. Lebreton and M.J.P.F.G. Monteiro (eds)
EAS Publications Series, 26 (2007) 79-89
DOI: 10.1051/eas:2007127

The Treatment of Overshooting in Stellar Modelling: Instantaneous and Diffusive Approach

P. Ventura

INAF - Osservatorio Astronomico di Roma, via Frascati 33, 00040 MontePorzio Catone (RM), Italy

(Published online: 20 June 2007)

Abstract
Convective overshoot is a physical mechanism for which no recipe based on first principles is available; hence the necessity of assuming some parametrisations, which undermine the predictive power of the current generation of stellar models. We evidentiate the non local aspects of the convective phenomenon particularly in the proximities of the convective borders, and identify some cases when the use of a diffusive rather than the classic instantaneous approach to describe overshooting is highly recommended.