Permanent Magnet System for PET Cyclotron

The recent paper is devoted to design, manufacturing and testing the permanent magnet system to be used for Positron Emission Tomography (PET) cyclotron. The using permanent magnet material instead of copper coils allows essential electric power savings during PET cyclotron operation, though it comes to some increasing construction cost. The main problem why until now permanent magnets were not used for PET cyclotron magnet system is huge magnetic force, making cyclotron assembling/disassembling and isochronous magnetic field adjustment very difficult. For presented magnet system that problem is solved by applying rotating system providing the magnetic field switch-off (reduction to practically zero level inside working aperture). It makes assembling and adjustment easy at force free conditions. The main parameters of permanent magnet system are as follows: the average field is 1.4 T, pole radius is 375 mm and weight is 900 kg. As it shown in paper the magnetic properties of constructed permanent magnet system does satisfy to specification for magnet system of typical 10 MeV cyclotron for PET radioisotope production.