This proposal is to investigate two main areas of solar research. The first is an improvement in our current knowledge of the thermodynamic structure and dynamical motions of the solar interior through the application of the tools of helioseismology. This goal will be reached through the continuation of an on- going, dedicated observing program which is located at the 60- Foot Solar Tower Telescope of the mount Wilson Observatory and through the continued analysis of the observations of solar oscillations which have already been obtained by that program. The second goal is the establishment of a two-station ground- based network for the observation of high-degree solar oscillations through the installation of an additional dedicated observing system, which will be located at the Crimean Astrophysical Observatory in the USSR. Through the installation and operation of this second station the PI will foster a strong collaboration between U.S. and Soviet helioseismologists and enhance the scientific return of our future U.S. observations beyond the return which we would get from the Mt. Wilson observations alone. The observations of the sun's surface motions will be converted into measurements of the frequencies, rotationally and magnetically induced frequency splittings, amplitudes and lifetimes of global solar oscillation modes. These results will then be inverted to map the sun's internal sound speed and angular velocity as functions of radius and latitude.
