Charged-particle measurements of $\rho $R symmetry at shock-bang time in NIF implosions

V. GLEBOV, P. RADHA, T. SANGSTER, \textit{LLE}, R. OLSON, R. LEEPER, SNL, J. KLINE, G. KYRALA, D. WILSON, \textit{LANL,} J. KILKENNY, A. NIKROO, GA, C. SANGSTER, \textit{LLE} The Wedge Range Filter (WRF) proton spectrometer was developed for OMEGA and transferred to the NIF as a National Ignition Campaign (NIC) diagnostic. In tuning campaign implosions containing D and $^{3}$He gas, the WRFs measure the spectrum of protons from D-$^{3}$He reactions. The energy downshift of the 14.7-MeV proton is directly related to total $\rho $R through the plasma stopping power. WRFs fielded simultaneously on the pole and equator measure low-mode polar $\rho $R asymmetries due to drive inhomogeneity. We find no correlation between shock $\rho $R symmetry and x-ray self-emission symmetry near peak compression for low polar modes. Adjacent WRFs are sensitive to high-mode asymmetries due to hydro instabilities; these have not been observed. This work was supported in part by the U.S. DOE, LLNL and LLE.