The influence of low-degree p-mode frequencies on the determination of the structure of the solar interior

Accurate measurements of the frequencies of low-degree acoustic oscillations provide valuable information about the structure of the solar core. We determine the radial resolution that can be achieved by direct inversions of frequency data sets recently obtained by various observers to find the hydrostatic parameters density, sound speed and a parameter of convective stability. The outcome of those inversions indicates that the outer part of the radiative zone of the Sun is similar to that of a solar model that takes account of helium settling against microscopic diffusion. From the two data sets with lowest estimated errors (those by Toutain & Fröhlich and Anguera Gubau et al.) there is some evidence for an error in the modelling of the energy-generating core, which could be accounted for by local material redistribution in the core. Another data set by Elsworth et al., however, is almost compatible with the core of the theoretical model.