Knockhyphen;on particle preheat in ion beam fusion targets

摘要

The elastic scattering of beam ions is shown to cause a potentially damaging flux of penetrating secondary knockhyphen;on particles. These secondary particles will be more penetrating than the primary ions if the atomic mass of the primary is larger than the secondary. A calculation, using the specific example of helium ions incident on an absorbing material containing hydrogen, reveals that the knockhyphen;on protons have a range greater than five times the range of the primary helium ions, and can cause a preheat problem. Thus, this effect is shown to be an important design consideration.