Heavy ion inertial fusion in Europe

Completion of the HIDIF-study in 1998 has been an important step in our understanding of critical issues of the RF-Linac/Storage Ring approach to heavy ion fusion pursued in Europe. One of the conclusions from this study was that the upgradability of the HIDIF-scheme to drive high-gain targets (for energy production) would benefit from an efficient reduction of the total beam phase space volume by a suitable non-Liouvillian technique. The implementation of an effective non-Liouvillian technique suitable for heavy ions is discussed in the context of the "Next Generation Facility" at GSI, which is understood as a significant extension of the present accelerator. Our studies have shown that Xe ⁴⁷⁺ stripping foil injection into a high-current accumulator ring could produce bunches of several tens of kilojoules. We also discuss the perspectives of using photo-ionization stripping in an upgraded HIDIF driver.