Study of an ion beam accelerator for the LINAC Research Center in Spain

Abstract

This thesis focuses on the study of an ion beam accelerator for the LINAC Research Center (LINCE) in Spain. The proposed superconducting LINAC operates at 72.75MHz and is designed to accelerate, in a first phase, light and heavy ions with mass-to-charge ratio in the range A/Q = 1 to 7 and beam energies from 500 keV/n to about 8MeV/n for heavy ions, and 40MeV for protons. LINCE developed from a previous project, the Linac Research Facility (LRF), an initiative to install a high-intensity, light- and heavy-Ion accelerator in the University of Huelva (Spain). The facility would be dedicated to basic nuclear research and multidisciplinary applications, notably using a high-intensity proton beam for radioisotope production of medical interest. Therefore, the main challenge of this thesis has been to devise a multi-ion LINAC accelerator capable of producing both high-intensity protons and heavy-ions with large A/Q. LINCE and LRF gathered a wide community of nuclear physicists and industrial shareholders from Spain and abroad, which contributed to different R&D activities coordinated by the local team at the University of Huelva. This thesis details the beam dynamics of the LINAC and the design of selected accelerator elements, with special emphasis in a key element of the facility: the radiofrequency quadrupole (RFQ). The codes TRACK, DESRFQ and MAD-X have been used for particle tracking simulations, COMSOL MULTIPHYSICS for radio-frequency (RF), thermal and structural analysis, and AUTOCAD INVENTOR for the mechanical design. This document is presented in seven chapters that cover beam dynamics studies, the design of accelerator elements, geometry models, RF simulations, and engineering studies of the structure including heating, cooling and mechanical displacements.