Some characteristics of moderate energy metal ion beam focusing by a high current plasma lens

Abstract

Articles you may be interested inDevelopment of an all-permanent-magnet microwave ion source equipped with multicusp magnetic fields for high current proton beam productiona) Rev. Sci. Instrum. 79, 02B317 (2008); Development of a high-current plasma lens for focusing broad beams of heavy metal ions Rev.Characteristics of focused beam spots using negative ion beams from a compact surface plasma source and merits for new applications

High-Current Heavy Ion Beams in the Electrostatic Plasma Lens

“…For the case of tantalum beam with diameter 10 cm, the maximum beam compression at the lens focus was approximately a factor of 30, with current density up to 32 mA/cm 2 . Similar results were obtained for a copper ion beam on the Kiev set-up, where the compression was a factor 15 -25 depending on the total ion beam current passing through the lens and the current density was up to 170 mA/cm 2 (see [6][7][8] for details).…”

“…The experiments were carried out at Kiev using the set-up described in detail in [6] and at Berkeley described in [7,8]. For ion beam formation we use a two-chamber MEVVA ion source with grid anode and a three-electrode, multi-aperture, accel-decel ion extraction system.…”

Space Charge Lenses for Intensive Ion Beams Formation

“…Fluctuations in a plasma lens worsen the quality of focusing and reduce an ion current density in a crossover of a beam [10]. Updating Gabor lenses were investigated and applied to transportation and focusing intensive beams of heavy ions [11,12]. It is of interest in connection with the problem of thermonuclear synthesis and a number of technological tasks.…”

Cross-field plasma lens for focusing of the Hall thruster plume

“…However, the PL has not previously been applied to Hall thrusters. Hall thrusters have highly divergent plumes with a large spread of ion energy (see figure 6), so the plasma that must be focused by our lens is substantially different than plasmas produced by gridded ion sources: the large beam divergence (45 • for common Hall thrusters [2]) creates sharper density gradients, the ion energy is significantly lower (<250 eV for this work compared with >5 keV for previous PL research [12,13]) and the non-uniform ion energy causes ion kinetic effects, which are discussed in section 5. The Hall thruster plume, therefore, presents a more difficult target for focusing, but even a modest reduction in the plume divergence would be technologically beneficial.…”