γ)O from White Dwarf Seismology

For many years, astronomers have promised that the study of pulsating white dwarfs would ultimately lead to useful information about the physics of matter under extreme conditions of temperature and pressure. We can now make good on that promise. Using observational data from the Whole Earth Telescope and a new analysis method employing a genetic algorithm, we empirically determine the central oxygen abundance of the helium-atmosphere variable white dwarf GD358. We use this value, combined with detailed evolutionary calculations of the internal chemical profiles to place constraints on the C(α, γ)O nuclear reaction cross-section.