Field fluctuation spectroscopy in a reverberant cavity with moving scatterers.
نویسندگان
چکیده
We report a study of transient ultrasonic waves inside a reverberant cavity containing moving scatterers. We show that the elastic mean free path and the dynamics of the scatterers govern the evolution of the autocorrelation of acoustic wave field. A parallel is established between these results and a closely related technique, diffusing acoustic wave spectroscopy. Excellent agreement is found between experiment and theory for a moving stainless steel ball in a water tank, thereby elucidating the underlying physics, and a potential application, fish monitoring inside aquariums, is demonstrated.
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عنوان ژورنال:
- Physical review letters
دوره 90 9 شماره
صفحات -
تاریخ انتشار 2003