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Guenther, David B.

Publications and source records attributed to Guenther, David B..

Post-main-sequence solar evolution

The standard evolution of a 1-solar-mass star from the zero-age main sequence to the helium flash is discussed. Two areas of solar-stellar research are examined which are presently in a state of rapid development: the theory of solar and stellar nonradial acoustic (p-mode) oscillations, which can be used to test the pressure stratification in the stellar interior; and the theory of the evolution of rotating stars, which predicts the evolution of surface rotational velocities and the mixing of chemical elements to the surface. Oscillations and rotation are closely interrelated because each individual p-mode is also split in frequency by internal rotation in the region through which it propagates. Observations of p-mode splittings can provide information on the state of rotation of the solar and stellar interiors.

Demarque, Pierre