Analyzing the Structure of Shell Modulations Around Peak Compression of Spherical Implosions

Programs were created to analyze the structure of shell modulations at peak compression of spherical implosions. Measurements of the modulations were taken by using absorption of titanium-doped layers placed at distances 1,5,7, and 9 pm from the inner surface of 20 pm-thick plastic CH shells filled with 18 atm of D ~ H ~ gas. These nonuniformities were measured using ratios of monochromatic target core images taken inside and outside the titanium 1 s-2p absorption spectral regions. The results show that the peak-compression, time-integrated areal-density modulations are higher at the inner shell surface, unstable during the deceleration phase of implosion, with the modulation level of 59 f 14%. The nonuniformities are lower in the central part of the shell, having a modulation level of 18f 5%. The outer surface of the shell, unstable during the acceleration phase of the implosion, has a modulation level of 52+20%. *This report has been adapted from "Radial Structure of Shell Modulations Near Peak Compression of Spherical Targets" by V.A. Smalyuk, S.B. Dumanis, F.J. Marshall, J.A. Delettrez, D.D. Meyerhofer, T.C. Sa~igster, and B. Yaakobi, submitted to Physics of Plasmas