Beam Injection Studies Using a Gabor Lens

Gabor lenses using a stable space charge cloud for focussing have several advantages compared with other lens systems. Especially for singly charged heavy ion beams at low velocities the theoretical performance of the lenses is superior [1]. On the other hand experiments at Fermilab and elsewhere [2] have only shown a small degree of lens filling compared to the theoretical prediction. In contrary newer experiments [3] demonstrated a much better degree of lens filling and substantially lower emittance growth. Therefore an experiment for the following HIDIF relevant subjects is underway [4]: • Gabor lens LEBT for RFQ injection, determination of lens filling and emittance growth • Extension of the experimental database by the use of a Gabor lens behind the RFQ (beam energy increased by a factor of 30). Investigation of the influence of the pulse structure on the space charge cloud and beam transport. • Investigation of interactions between high power beams and solid material, relevant for the investigation of beam losses observed in high current storage rings. The schematic layout of the experiment is shown in fig. 1.