Xii. Physical Acoustics A. Nonlinear Distortion of Sound Waves in Liquid Helium
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چکیده
Some initial results in this investigation were presented in Quarterly Progress Report No. 54, pages 152-154. The photographs (Fig. XIII-2, p. 153) indicated a roughly linear spatial growth in the second harmonic of an initially monochromatic finite wave, followed by a steep exponential decay. It is possible that some of this nonlinear distortion occurs at the crystal surface as the wave bounces back and forth between the crystals. In order to 10 -avoid this possible mixing at the crystal surfaces, the 9 multiple-reflection method
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تاریخ انتشار 2009