Scanning transmission ion microscopy computed tomography (STIM-CT) for inertial confinement fusion (ICF) targets

ICF target quality control in the laser fusion program is vital to ensure that the energy deposition from the lasers results in uniform compression and minimization of Rayleigh–Taylor instabilities, which requires surface finishes on the order of submicron-scale. During target fabrication process the surface finish and the dimensions of the hohlraum need be well controlled. Density variations and nonspherical or nonconcentric shells might be produced. Scanning transmission ion microscopy computed tomography (STIM-CT) is able to reconstruct the three-dimensional quantitative structure of ICF targets a few tens of micrometers in size. Compared to other types of probe techniques, the main advantage of STIM-CT is that quantitative information about mass density and sphericity can be obtained directly and non-destructively, utilizing specific reconstruction codes. We present a case of ICF target (composed of polyvinyl alcohol) characterization by STIM-CT in order to demonstrate the STIM-CT potential impact in assessing target fabrication processes.

► ICF target quality requires surface finishes on the order of submicron-scale.
► In STIM inner and outer wall profile can be mapped.
► In STIM the thickness and nonconcentricity of shell-wall in ICF targets can be measured.
► STIM-CT is a powerful method for obtaining three-dimensional density maps within ICF targets.
► STIM-CT can obtain internal structure with identifying non-uniformities in the ICF targets.