Chamber, target and final focus integrated design

Liquid wall protection, which challenges chamber clearing, has advantages in Heavy Ion Fusionʹs (HIF) main line chamber design. Thin liquid protection from X-rays is necessary to avoid erosion of structural surfaces and thick liquid makes structures behind 0.5 m of flibe (7 mean free paths for 14 MeV neutrons), last the life of the plant. Liquid wall protection holds the promise of greatly increased economic competitiveness. The illumination must be compatible with liquid wall protection. The “best” values for driver energy, gain, yield and pulse rate comes out of well-known trade-off studies to arrive at the minimum cost of electricity. In order to reduce the driver cost and therefore reduce the cost of electricity, driver designers are attempting to reduce driver energy from the old 10 GeV value and increase the number of beams to about 200 to illuminate recent target designs from two sides. We have not yet succeeded in coming up with an integrated chamber design compatible with 200 beams. The present design iteration and future ones will depend on several key assumptions, such as jet surface smoothness and rapid chamber clearing. Before HIF can be considered feasible and economical, we need an integrated chamber, target, and final focus design and successful resolution of key technical issues by the chamber R&D efforts.