The High Temperature Experiment for Accelerator Inertial Fusion

The High Temperature Experiment (HTE) is intended to produce temperatures of 50-100 eV in solid density targets driven by heavy ion beams from a multiple beam induction linac [1]. The fundamental variables (particle species, energy, number of beamlets, current and pulse length) must be fixed to achieve the temperature at minimum cost, subject to criteria of technical feasibility and relevance to the development of a Fusion Oriver. The conceptual design begins with an assumed (radiation-limited) target temperature and uses limitations due to particle range, beamlet perveance, and target disassemnbly to bound the allowable values of mass number (A) and energy (E). An accelerator model is then applied to determine the minimum length accelerator, which is a guide to total cost. The accelerator model takes into account limits on transportable charge, maximum gradient, core mass per linear meter, and head-to-tail momentum variation within a pulse. For specified target temperature, T, spot size r and beamlet number N, the particle energy E must lie above a critical value which only weakly depends on A (Ecrit ¿A·2). The minimum length accelerator is associated with the high mass end of this line, determined by a condition on range in the target. Singly charged potassium ions with E = 132 MeV are a good match to an 80 eV temperature.