Effects in Heavy-Ion Radiation Damage on Target Lifetimes in UNILAC Experiments

摘要

This work is mainly the result of a literature research on effects of radiation damage occurring in targets commonly used in heavy-ion bombardments. Concepts and models for the description of radiation damage effects in solids as well as experimental methods for the quantitative characterization of such effects are reviewed. Some of these concepts are applied to the practical case of bombardments of exp 248 Cm-metal targets or refractory element substrates with high-intensity beams of approx. equal to 7 MeV/n exp 238 U-ions. Experimental observations during these bombardments, evaluation of macroscopic properties of the bombarded targets, as well as results from simulations of the bombarding conditions by electron-beams and low-energy heavy-ion beams are reported. This results in several conclusions concerning the limited life-time of the exp 248 Cm-targets and suggestions for future tests and target modifications. (ERA citation 07:044493)