Investigation of ion beam extraction from the U-400 cyclotron by the stripping method

The extraction and transport of ions in a wide energy range along the same ion channel from the U-440 cyclotron are investigated. The approximation of radial distribution of the cyclotron magnetic field by polynomials using the least square method is used in the programs for calculating extraction parameters. Sizes, position of centres of extracted beams and direction of ion velocity vectors versus foil azimuth are determined. The calculations were carried out for stripping coefficients 3; 3.5; 4 within the 1.40-1.75 m range of extraction radii. The effect of correcting magnets, compensating and focusing channels on the extraction efficiency is investigated. The theoretical and experimental results are compared. The investigations performed permit to optimize the system of ion extraction from the U-400 cyclotron and point out the ways to extend the range of ions and energies