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Light Diffraction and its Use in the Study of Acoustic Parametric Oscillations. Michael S. McPherson University of Mississippi National Center for Physical Acoustics University, MS 38677. Colleagues. Mack Breazeale, Distinguished Professor of Research, UM, University, MS
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Light Diffraction and its Use in the Study of Acoustic Parametric Oscillations Michael S. McPherson University of Mississippi National Center for Physical Acoustics University, MS 38677
Colleagues • Mack Breazeale, Distinguished Professor of Research, UM, University, MS • Alem Teklu, Ph. D., LSU, Asst. Prof., Charleston
Diffraction showing existence of subharmonics Simultaneous Diffraction Patterns and Schlieren Images (a) without, (b) with Parametric Oscillation
Diffraction before and after the onset of of parametric resonance at different frequencies and amplitudes
Reflector Driver l0 The Periodically Varying Cavity
Conclusions • Results of a new investigation of parametric resonance in an acoustic resonator are presented • Measurements of the threshold drive amplitude frequency dependence show an apparent contradiction with previous results • Resonators with differing lengths can result in the onset of parametric amplification in different regions of instability • These differing regions of instability account for the differences in the observed data trends