Experimental measurements of hydrodynamic instabilities on Nova of relevance to astrophysics

Large lasers such as Nova allow the possibility of achieving regimes of hig h-energy densities in plasmas of millimeter spatial scales and nanosecond t imescales. In those plasmas where thermal conductivity and viscosity do not play a significant role, the hydrodynamic evolution is suitable for benchm arking hydrodynamics modeling in astrophysical codes. Several experiments o n Nova examine hydrodynamically unstable interfaces. A typical Nova experim ent uses a gold millimeter-scale hohlraum to convert the laser energy to a 200 eV blackbody source lasting about a nanosecond. The X-rays ablate a pla nar target, generating a series of shocks and accelerating the target. The evolving areal density is diagnosed by time-resolved radiography, using a s econd X-ray source. Data from several experiments are presented and diagnos tic techniques are discussed.