Density measurements of heavy-ion-beam-induced stress waves in solid matter by a sensitive laser deflection technique.

We present a sensitive density diagnostic based on the deflection of a laser beam by refractive index gradients. The method is used to investigate stress waves in plexiglass, created by the irradiation of multilayered metal–plexiglass targets with intense relativistic heavy-ion beams. Measured laser deflection angles are of the order of 1 mrad, with a resolution of the apparatus of 50 μrad. Results are in excellent agreement with interferometric measurements. The deflection technique is superior to an imaging interferometer in terms of simplicity and sensitivity. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]