Production and characterization of doped mandrels for inertial-confinement fusion experiments

A key feature of current inertial‐confinement fusion (ICF) experiments is the incorporation of dopant atoms into the thin polymer microshell which, in a finished ICF capsule, forms its inner wall. These dopants provide a spectroscopic signal during the implosion that can be used to diagnose the degree of mix at the capsule–fuel interface. The high‐Z dopants can also be used to directly image the fuel–pusher interface. The current status of doped mandrel development is reviewed, with a focus on the mandrel surface smoothness. With the development of unique surface mapping characterization tools which will be described, it has been discovered that mandrel surface smoothness is a function of the polymers used to form the mandrels. In this report it will be shown that Cl‐doped mandrels produced from a blend of polystyrene and poly(p‐chlorostyrene) are rough on a length scale of 10’s of microns with amplitudes of as much as a 100 nm. The origin of this roughness will be discussed, and it will be shown that thi...