The spectrum of gravity modes as a function of the solar structure: Model with a mixed core

The asymptotic properties of the gravity modes of solar models with a mixed core have been investigated. Such models have been constructed by Gavryusev and Gavryuseva (1984) to explain the low value of the observed neutrino flux (Cleveland, Davis, and Rowly, 1984). The strong enhancement of the Brunt-Väissälä frequency in the region of variable chemical composition at the boundary of the mixed core gives rise to a nonequidistant spectrum of gravity mode periods (Figure 1), contrary to the case of standard models. These models do not satisfy the helioseismological constraints given by the p-modes. However, the peculiar behavior of the numerically computed periods of the gravity modes is interesting to analyze, in view of observational detection in solar and stellar spectra.