Measuring surface deformations in magnetic fluid by radioscopy

We present a quantitative method, capable of measuring the three-dimensional shape of a fluid surface. Utilizing the attenuation of x-rays in magnetic liquids, we are able to map amplitude and relief of large wave crests, a regime which is not accessible by the common optical methods. The technique is applied for measuring the static surface deformations of the Rosensweig instability. It will also be useful for measuring the surface profile of the Faraday instability in magnetic liquids, in standard fluids, in liquid metals, or even in granular material. (C) 2001 American Institute of Physics.