Fast Ignition with Laser-Driven Ion Beams

We report on the US research program on fusion fast ignition (FI) using laser-driven ion beams. Compressed DT fuel can ignite with beams of quasi-monoenergetic ions, such as carbon at $\sim $ 500 MeV. The FI simulations that set the requirements and guide our work are shown. The mechanisms that enable a short-pulse laser to drive the ignitor ion beam are summarized, especially how the $\sim $ GeV ion energies required are attained. We also aim to reduce the C-ion energy spread to $\sim $ 10{\%} over the energy range of $\sim $ 0.1 -- 1 GeV. The latest 1, 2 and 3 dimensional simulations on ion acceleration are shown. Those simulations guide our ion experimental work at the Los Alamos Trident laser facility. Our experimental results are summarized, followed by a discussion of the salient issues and the way our project is addressing them.