Isochronous cyclotron

Strijckmans K (2001) The isochronous cyclotron principles and recent developments. Computerized Medical Imaging and Graphics 25 69-78. 

The first high-resolution study of the transmission resonances in was carried out at d = 9.73 MeV at the Debrecen 103-cm isochronous cyclotron and at = 13.0 MeV at the Munich Tandem accelerator. Enriched (97.6-99.89%) 88-250 pg/cm thick targets of were used. 

In isochronous cyclotrons, the magnetic field is increased along the radius at the rate of the relativistic increase of the mass of the accelerated particles. The time required for one revolution is constant during the acceleration, and a fixed-frequency RF system can be used. For vertical focusing, the magnetic field is appropriately shaped with radial or spiral sectors... 

Pole faces of the isochronous cyclotrons the hills" are the sectors. Between the hills, the magnetic field is made stronger by reducing the pole gap... 

In a perfectly isochronous magnetic field, the particles move fully in phase with the RF field. If a particle loses the right phase for any reason, there will be a phase slip in one direction or the other. In classical and isochronous cyclotrons, it is not possible to stabilize the phase of the gap crossing and the acceleration continues until the phase error becomes so great that deceleration occurs. 

The isochronous cyclotrons can accelerate different particles from protons to the ions of the heaviest elements. The energy of the particles is determined by the setting of the cyclotron, and that can be changed in a wide range. The relativistic behavior of the particles can be neglected for the sake of these considerations. The heavy-ion cyclotron can be specified by the so-called factor determining the maximum kinetic energy of the ions by the relation... 

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