Conceptual design of magnetic field mapping in polar coordinate for DECY 13 cyclotron

Abstract Center for Accelerator Science and Technology (CAST) BATAN conducting a project on design and construction of 13 MeV proton cyclotron (DECY-13), which eventually will be used for radioisotope production. This cyclotron has several main components, one of them is a magnetic system that has been installed at the end of 2014. In the initial stage, magnetic field mapping was carried out with a mechanical structure in the x and y directions (Cartesian coordinate) using 2 hall probes. However, the results achieved have not been able to show the distribution of magnetic fields in accordance with the design specifications because the energy of beam path less than 3 MeV. The new mapping system was proposed for the DECY-13 magnet, using a hall probe that mechanically moves in angular and radial steps which are 1 degree and 5 mm, respectively. Based on the calculation, the mapping process required about 9 hours for 34,560 data, this number of data is 17% higher than the previous mapping system. Instrumentation of this system has 0.1 Gauss of error and 0.01 Gauss of resolution. The radial mapping provides better accuracy and more compatible with a further magnetic field analysis than the Cartesian.