Robust heavy-ion-beam illumination against a direct-drive-pellet displacement in inertial confinement fusion

Nonuniformity of heavy-ion-beam (HIB) illumination is one of key issues in the HIB inertial confinement fusion (ICF): implosion symmetry should be less than a few percent in order to compress a fuel sufficiently and release fusion energy effectively. In this paper a new HIB illumination scheme is presented in order to realize a robust illumination scheme against a displacement of a direct-driven fuel pellet in an ICF reactor. It is known that the HIB illumination nonuniformity is sensitive to a little pellet displacement from a reactor chamber center; a pellet displacement of only 50–100μm was tolerable in the conventional HIB illumination schemes. In this paper by three-dimensional computer simulations a new robust HIB illumination scheme was found, in which a 200–300μm displacement is allowed.