Development of a high-current laser ion source for induction accelerators

We have developed a high-current laser ion source that can provide low-char ge-state ions for induction accelerators. A frequency-doubled Nd:YAG laser (lambda=532 nm) irradiated a copper target with relatively low intensities of 10(8)-10(9) W/cm(2). The laser-produced plasma supplied a large number o f Cu+ and Cu2+ ions over 10(14) ions/cm(2) at a distance of 10 cm from the target. We have successfully extracted high-current copper beams over 0.1 A /cm(2) using an inductive acceleration module. The beam emittance measured by a pepper-pot method was about 40 pi mm mrad. (C) 2000 American Institute of Physics. [S0034-6748(00)68802-0].