A pulsational study of crystallized white dwarf stars

The DAV BPM 37093 should have a substantially crystallized core based on its mass and temperature. Using this as a motivation, we examine the way in which a crystalline interior affects the nonradial g-mode frequencies of a white dwarf star. We confine ourselves to a relatively massive model within the DA instability strip (M-* = 1.1M.), since crystallization in this temperature range should be important only for high-mass white dwarfs. We find that crystallization has a significant effect on the mean period spacing of adjacent radial overtones, of order 10-30 %. Thus, a correct pulsational treatment; of crystallization is vital if we are to make reliable asteroseismological measurements of a given stars' properties.