Evolutionary models for pulsation studies of white dwarfs

A large grid of equilibrium models suitable for adiabatic and nonadiabatic seismological investigations of pulsating white dwarfs of the DAV and DBV types is presented and discussed in detail. The basic structure of the models is that of a layered configuration consisting of an almost pure carbon core surrounded by an almost pure helium layer, itself surrounded by an almost pure hydrogen layer. Models are computed for three masses, and the helium layer mass is varied. The effects of varying the assumed convective efficiency are investigated. A special sequence is computed to explore the effects of changing the composition gradient scale height in transition regions. Models using two different sets of radiative opacities for the same compositions are obtained to test the sensitivity of the pulsation properties to this component of the constitutive physics. These experiments constitute by far the most extensive study that has been performed to provide suitable models for pulsating white dwarfs.