Deterministic Fabrication and Characterization of Fill Tube Surrogate Targets for OMEGA Experiments Using a Polymer Stalk

Abstract

Equipment and techniques have been developed for the fabrication of fill tube surrogate targets for OMEGA experiments. The fill tube is attached manually by heating 4000 MW poly-α-methylstyrene in a fixed reservoir, which can be touched onto the capsule surface and pulled into the shape of a fill tube. The joint is uniform and robust with diameters no less than 20 μm. A series of surrogate fill tubes can be achieved by modifying temperature and technique with a diameter reproducibility within 5 μm. After attachment, the capsules are mounted onto a calibrated stage to trim the length of the surrogate to specifications. Characterizing the surrogates involved positioning the polymer stalk to measure the fillet diameter, stalk diameter, and length at orthogonal orientations. Details of the heating and pulling techniques will be discussed as well as a description of the polymer reservoir.