Heavy-ion inertial fusion: Suggested experiments on disk heating and beam transport using accelerator test facilities

Our calculations suggest that experiments relating to disk heating, as well as beam deposition, focusing and transport can be performed within the context of current design proposals for accelerator test-facilities. Since the test-facilities have lower ion kinetic energy and beam pulse power as compared to reactor drivers, we achieve high-beam intensities at the focal spot by using short focal distance and properly designed beam optics. In this regard, the low beam emittance of suggested multi-beam designs(l, 2) are very useful. Preliminary results suggest that intensities close to 10¹⁴ W/cm² are achievable. Given these intensities, deposition experiments with heating of disks to greater than a million degrees Kelvin (100 eV) are expected. We could also expect as much as 1–3 kA of incident ion current on these disks with beam intensities almost comparable to that of reactor targets. Thus, if any anomalous plasma effects on deposition emerge, the conditions should be available for testing some of them. We might also note that these deposition experiments have low ion kinetic energy per nucléon. About 4–5 MeV/nucleon is achievable if lighter ions such as sodium were used. But for lighter ions, plasma effects in deposition might be more severe because heavy-ion beams are more "stiff".