A New Technique for Probing Convection in Pulsating White Dwarf Stars

In this paper we demonstrate how pulsating white dwarfs can be used as an astrophysical laboratory for empirically constraining convection in these stars. We do this using a technique for fitting observed nonsinusoidal light curves, which allows us to recover the thermal response timescale of the convection zone (its "depth"), as well as demonstrating how this timescale changes as a function of effective temperature. We also obtain constraints on mode identifications for the pulsation modes, allowing us to use asteroseismology to study the interior structure of these stars. Aspects of this approach may have relevance for other classes of pulsators, including the Cepheids and RR Lyrae stars.