Time-resolved quasi-elastic laser scattering measurements

Time-resolved quasi-elastic laser scattering (QELS) experiments [306, 307] allow the measurement of the dispersion law (the relation between the frequency of capillary waves, co, and their wavelength, In/k). To derive the dispersion law theoretically, one must consider the dynamics of the two degrees of freedom - the position of the surface, z = (x, y, t), and the fluid velocity. In the limit of small viscosity, such a theory [291] gives... 

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