Shadowgraphy measurements on the heavy ion beam interaction with solid targets

At the HHT experimental area, strongly coupled plasmas are created by the interaction of the SIS heavy ion beams with solid targets. To obtain a high energy deposition in the target, the ion beam is focused by the plasma lens [1] to diameters smaller than 1 mm in the focus. The generated plasmas have densities close to the solid state density, volumes of several mm and temperatures up to 1 eV. The characterization of the matter under such extreme temperatures and pressures is of relevance for equation of state (EOS) studies, in astrophysics for understanding the formation of heavy elements in supernovae, for designs of future heavy ion driven Inertial Fusion Experiments (IFE) and others. A wide range of optical diagnostics, such as shadowgraphy, time resolved spectroscopy in visible and VUV ranges, and schlieren techniques were recently developed to study the target behavior at the interaction with the ion beam. Up to now, metallic and cryogenic gas crystal targets [2] were used for the ion beam heating experiments, characterized by backlighting shadowgraphy and time resolved spectroscopy. For these experiments the backlighter was a high energy (250 J) Xe flashlamp and the target dynamics was detected with a fast multiframing camera, capable to acquire simultaneously eight frames with an exposure time above 10 ns.