4aPA5. Absorption of sound by noise in one dimension.

Session: Thursday Morning, May 16

Time: 9:00

Author: Andres Larraza
Location: Dept. of Phys.---Code PH/La, Naval Postgrad. School, Monterey, CA 93943
Author: Bruce Denardo
Location: Univ. of Mississippi, University, MS 38677


Experimental results are presented for the excess attenuation of mono-frequency waves in the presence of high-intensity noise in one dimension. The theory by Rudenko and Chirkin predicts a Gaussian attenuation of a weak signal in the presence of shockless noise, thus showing that in one dimension translational invariance has been broken. The theory is modified to incorporate wall losses providing, only then, excellent agreement with experiment. The agreement is shown as the frequency, noise level, and distance from the source are varied. In addition, the spectral intensity of the high-frequency tail of fully developed shockless noise is observed to be an f[sup -3] power law in the frequency f, in accord with theory. This power law is a consequence of the far off equilibrium nature of the system. [Work supported by ONR.]

from ASA 131st Meeting, Indianapolis, May 1996