Megabar liner experiments on Pegasus II

Using pulsed power to implode a liner onto a target can produce high shock pressures for many interesting application experiments. With the Pegasus II facility in Los Alamos, a detailed theoretical analysis has indicated that the highest attainable pressure is around 2 Mbar for a best designed aluminum liner. Recently, an interesting composite liner design has been proposed which can boost the shock pressure performance by a factor of 4 over the aluminum liner. This liner design was adopted in the first megabar (Megabar-I) liner experiment carried out on Pegasus last year to verify the design concept and to compare the effect of Rayleigh-Taylor instabilities on liner integrity with the code simulations. The authors present briefly the physical explanation why the composite liner provides the best shock pressure performance. The theoretical modeling and performance of Megabar-I liner are discussed. Also presented are the first experimental results and the liner design modification for their next experiment.