Cryogenic Target Racks
The seven-slot target racks hold cryogenic target assemblies in place while the deuterium–tritium (DT) filling operation occurs. Using oxygen-free, high-conductivity copper (OFHC), the rack is disposable for each DT fill, as the part becomes tritium contaminated beyond the level worth reusing. Targets are filled following a recipe to pressures of hundreds of atmospheres and temperatures down to 18 K. Once the fill process is complete, the target assemblies are moved from the rack into moving cryostats for final DT ice layering and characterization. As with other unique precision parts, the target racks were designed and produced in-house, with machining performed by Scott Gross on the Haas, four-axis CNC Office Mill and Hass CNC Office Lathe, hand masked, bead blasted, and electropolished. All critical-to-function features were performed in our Quality Control Lab by Cliff Mathews.