The paper presents a parameter study of implosion, ignition conditions, burn and gain of a single-shell, multi-layered, heavy-ion-beam driven ICF target as a function of input pulse parameters including input power, input energy, incident ion range and pulse shape. It is shown that a prepulse is necessary to achieve central ignition in the fuel. Moreover, the target gain is very sensitive to the level of the prepulse power. The minimum power in the main pulse required to ignite this target is 500 TW. Some calculations are also done by using different ignitor masses to help in understanding the process of spark formation under different conditions. The effect of the shortening of the range of the incident ions on the target gain and the ignition conditions is also considered. These simulation results are explained in terms of the theory of isentropic compression and the theory of shock waves. In this way, it is shown how ignition in such a target is obtained and how its performance is optimized in order to achieve maximum fractional burn and gain.

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In the overall design of an inertial fusion reactor driven by ion beams or lasers the target design plays a central role. The concept of central ignition is used to reduce the input energy of the driver as much as possible. In this respect, the range of the 3.5 MeV alpha particles at 1-20 keV released by the fusion reactions in D-T is crucial for estimating the driver parameters. Further, for the calculation of the pellet gain and the burn processes, the ranges of alpha particles at temperatures up to 200 keV and at densities up to 1000 g*cnf 3 must be accurately known. The 14.1 MeV neutrons produced during the D-T reaction can collide with the deuterium and tritium ions and produce suprathermal knock-on ions which then slow down in the background plasma. This effect must also be calculated, especially for reactor-size pellets for which the pellet pR is comparable to the neutron mean free path. The stopping power of low atomic fusion products and deuterium and tritium ions in D-T is calculated, using the dielectric function theory for the stopping power of electrons. The theory of the energy deposition of ions in fully ionized, quantum and classical, ideal and non-ideal dense plasmas is reviewed. The GORGON computer code is used for the numerical calculations. The results obtained are compared with the results of other authors and with their theoretical methods.

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Analytic and numerical solutions for the problem of the interaction of intense ion beams with matter in the form of plane targets are considered in this paper. The theory of the interaction of protons with matter at low energies is discussed and calculations are presented for the energy loss of protons in aluminum and gold. Zero- and one-dimensional models are developed and the results are compared to numerical simulations carried out with the one-dimensional Lagrangian hydrodynamic code medusa [Comp. Phys. Comm. 1, 271 (1974)], which has been extended to include the various physical effects needed to carry out realistic simulations of the interaction of ion beams with matter. The theory and simulation of the acceleration of foils by intense ion beams is also considered and representative results are given. The theoretical results are used to investigate the optimum conditions in which to carry out stopping power experiments for ions in hot, dense plasmas, so that the theory can be tested. These results are needed in order to perform more realistic pellet calculations for inertial fusion.