NEW THEORIES OF CONVECTION IN THE CONTEXT OF A RECENT ANALYSIS OF THEDBV WHITE-DWARF GD-358

We present updated evolutionary calculations for carbon-oxygen DB whit e dwarfs using the self-consistent model for turbulent convection rece ntly developed by Canuto, Goldman & Mazzitelli (CGM). To this end, we employ a detailed stellar evolutionary code in which we include a new equation of state for helium plasmas computed by Saumon, Chabrier & Va n Horn as well as new OPAL radiative opacities. The present study is a imed at assessing the compatibility of the CGM model with the recent e ffective temperature redetermination of the pulsating DB white dwarf s tar GD 358. This star defines the blue edge of the DB white dwarf inst ability strip. Using thermal time-scale arguments, we find that the DB blue edges given by the CGM fit to the effective temperature of GD 35 8 are much better than those given by the previous Canuto & Mazzitelli model.