Evolution of the pulsation properties of hot pre-white dwarf stars.

The authors have solved the equations of linear, nonradial adiabatic oscillation for evolutionary pre-white dwarf (PWD) models. They have computed periods, eigenfunctions, weight functions, and rates of period change (dP/dt) for high-order dipole and quadrupole gravity mode oscillations in spherical, nonrotating PWD models with M_* = 0.60 - 0.95 M_sun; and log(L/L_sun;) = 3.0 - 1.0. The recently measured period decrease of the pulsating star PG 1159-035 is consistent with the limits provided by these models.