The LANL Research Program on Ion-Based Fast Ignition*

A few LANL research programs are engaged in activities that are being coordinated as a research program to evaluate fusion fast ignition (FI) initiated by laser-driven ion beams heavier than protons. Compared to protons, FI based on heavier ions has the potential advantage of a more localized energy deposition, which could minimize the required total ion-beam energy ($\sim $ 10 kJ). This FI scheme also requires about 100-fold fewer ions to deliver the necessary energy to ignite. Key ingredients necessary to implement this scheme include the generation of a sufficiently monoenergetic beam, at a sufficiently high ion energy, along with a sufficiently high conversion efficiency of laser to beam energy. Moreover, a better understanding of ion stopping power in dense matter is necessary. The research elements addressing these issues, both in the area of theory and experiment, are summarized in this presentation.