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Updated: Jul 7, 2026

A Stable Phantom Material for Optical and Acoustic Imaging
Published on: June 16, 2023
Enhanced sound transmission from water to air at low frequencies
B Edward McDonald1, David C Calvo
1Naval Research Laboratory, Washington, DC 20375, USA. mcdonald@sonar.nrl.navy.mil
Abstract:
Excitation of acoustic radiation into the air from a low-frequency point source under water is investigated using plane wave expansion of the source spectrum and Rayleigh reflection/transmission coefficients. Expressions are derived for the acoustic power radiated into air and water as a function of source depth and given to lowest order in the air/water density ratio. Near zero source depth, the radiation into the water is quenched by the source's acoustic image, while the power radiated into air reaches about 1% of the power that would be radiated into unbounded water.
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