A Study of the Five-Minute Oscillations, Supergranulation, and Related Phenomena in the Solar Atmosphere.
CALIFORNIA UNIV BERKELEY DEPT OF PHYSICS
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In the early 1960s two new types of motion in the suns atmosphere were discovered the 5-minute oscillations and the supergranulation. The 5-minute oscillations consist of a predominantly vertical hydrodynamic wave motion in the photosphere and chromosphere with amplitudes around 500 meterssec. The supergranulation consists of a series of convective cells, 30,000 km in diameter, in which material rises at the center, flows horizontally outward, and falls at the boundaries. The horizontal motion in the supergranulation was clearly observed, but its vertical motion was observed only marginally at best. The observations that form the basis of this thesis were made at the Mt. Wilson Observatory 150-foot solar telescope. The observing equipment is described in detail, including the optics, guiding and scanning system, spectrograph, magnetograph, electronics, and data system. The observing procedure used in these observations is carefully described, as is the method of calibrating the doppler, Zeeman, and intensity signals. The initial data reduction is also discussed. Various measurements of the size and lifetime of the 5-minute oscillations are reported. Author