Tishkin S. Combined focusing by RF field in channels of a linear accelerator

The dissertation provides new solutions to a very important scientific problem of stable acceleration of charged particle beams by radio frequency electric fields in ion linear accelerators with low particle losses in the process of acceleration. To solve the problem, a method for radial-phase stability of particle motion based on a combination of phase-alternating and radio frequency quadrupole focusing has been proposed. Several ways have been suggested for implementing the combined focusing using Interdigital and Cross-Bar H-structures. It has been shown that combined focusing by rf field is highly competitive, in terms of current trapping, with focusing by conventional methods based on the usage of phase stability and exter-nal focusing devices, more reliable and much simpler in realization.