Magnetic Field Calculation and Shimming of the Self–extraction Cyclotron
نویسندگان
چکیده
The self-extraction cyclotron is a 14 MeV H+ machine from which the beam extracts without a deflector. This is achieved with a special shaping of the magnetic field. Detailed 3D magnetostatic models have been constructed of this cyclotron, in order to accurately calculate the extraction process. Shimming of removable pole tips has been used to isochronize the machine and to remove harmonic errors. A software simulation of the shimming has been made, in order to accelerate the convergence of this process. First extracted beam has been obtained. There is good agreement between the calculations and measurements. Results of TOSCA calculations, mapping and shimming are presented.
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