Spatial distribution of Ti-tracer in OMEGA implosions

We discuss the observation and analysis of implosion core spectrally-resolved image data from Ti-doped, deuterium-filled OMEGA direct-drive implosions. The targets were spherical plastic shells of varying thicknesses and gas pressures with a thin Ti-doped tracer layer at the fuel-shell interface. The spectral features from the tracer are primarily observed at the collapse of the implosion and recorded with three identical gated, multi-monochromatic x-ray imager (MMI) instruments fielded along quasi-orthogonal lines-of-sight. The gated data show simultaneous emission and absorption features associated with Ti K-shell line transitions. The spectrally-resolved images recorded with MMI were processed to obtain narrow-band images\footnote{T. Nagayama, et. al, J. App. Phys. 109, 093303, (2011).} and spatially-resolved spectra characteristics of annular regions on the image\footnote{T. Nagayama, et al, Phys. Plasmas 19, 082705, (2012)} Detailed spectroscopic analysis of the spatially-resolved line spectra yields electron temperature and density of the plasma in the core. An Abel inversion of the image's intensity profiles and a complementary analysis method of the spatially-resolved Ti x-ray lines reveal the spatial distribution of the Ti in the core, and provide information on the symmetry and hydrodynamic stability of the implosion.