FOCUSING BEHAVIOR OF PLASMA LENSES COMPARED TO CONVENTIONAL QUADRUPOLE SYSTEMS

Intense heavy ion beams focused to small spots are powerful tools to d eposit a high specific deposition power in a target. A hot dense targe t plasma is formed which is available for further experimental investi gation and to study beam-target interaction phenomena with relevance f or the physics of inertial confinement (ICF) fusion. For a given set o f beam parameters the minimum focused spot size is mainly limited by t he focusing strength of the final lens system. Besides systems consist ing of conventional quadrupoles also cylindrically symmetric, ''active '' plasma lenses have been built and tested at GSI attempting to overc ome the limitations of quadrupole focusing. Superiour fine-focusing pr operties of plasma lenses have been demonstrated and a remarkable prec ision has been found. In this paper a quantitative comparison of the f ocusing strength of plasma lenses with conventional magnetic quadrupol es is presented.