AN ION BEAM MATCHING TO A LINAC ACCELERATING-FOCUSING CHANNEL

A modern linear accelerator of ions is a long chain of different accelerating-focusing structures. The design of new linacs, as well as an upgrade and optimization of operating facilities, requires precise and reliable beam matching with the subsequent sections. Proper matching of the beam to the channel allows to improve the performance of the whole linac and to reduce the specific costs. Additionally it helps to avoid particle loss in high energy high intensity linacs and to reduce activation. Generally a matching algorithm combines precisely measured or calculated accelerating-focusing external fields and experimentally obtained details of the beam parameters (energy, current, and emittance) with an advanced code for beam dynamics simulations including space charge effects. Measurements and experimental results are introduced into a code as input data. The described algorithm has already been successfully implemented for several GSI projects: upgrade of the GSI heavy ion linac UNILAC, ion linac for the cancer therapy, proton linac for the FAIR facility, GSI linac for deceleration of the heavy ions (HITRAP), facility for laser acceleration of ions (LIGHT) and others. Measured data and results of beam dynamics simulations leading to an achieved improvement of the linac performance are presented.