The influence of turbulence on the solar p-mode frequencies

نویسنده

  • S. Böhmer
چکیده

Calculations were carried out in order to probe the influence of turbulence on the solar oscillation frequencies as a possible explanation of the difference between observed and computed mode frequencies. As a first step the analysis is restricted to the radial oscillation modes. Corrections to the oscillation equations due to turbulence are determined with the help of perturbation theory, and the influence on the solar mixing length model is tested by recalculating the solar convection zone. The first interesting result is that the first order corrections in the oscillation equations arising from the Reynolds stress do not simply produce a blueshift. For small frequencies, due to the form of the turbulent velocity field, we can observe a redshift of the frequencies as well. The zeroth order corrections seem to have only a small influence on the results. For the turbulent modifications of the speed of sound (i.e., the correlation of density and temperature fluctuations), that were predicted as redshifted in a previous paper we find on the other hand, when we include the zeroth order corrections in our model as well, the difference turns into an overall blueshift.

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تاریخ انتشار 1998