In an isochronous cyclotron, the magnetic field is shaped by using precisely machined steel magnet poles. This variation provides a focusing effect as the particles cross the edges of the poles. In an FFA, separate magnets with alternating directions are used to focus the beam using the principle of strong focusing .

2001年3月1日 · An isochronous cyclotron overrules the problems related to relativistic mass increase during acceleration. Harmonic operation and negative (vs positive) ion acceleration (and extraction) are explained, as they make dedicated PET cyclotrons a …

The world’s largest cyclotron, at the TRIUMF laboratory in Vancouver, B.C., Can., is a sector-focused machine. Its magnet, which weighs 4,000 metric tons and is 18 metres (59 feet) in diameter,…

近年来比利时IBA公司推出新颖的“旋流30" (Cyclone30)型加速器，它可产生30MeV的质子，且能量可在15-30MeV范围内连续变化，引出的外束流强可达350-500μA,适用于生产 11 C, 13 N， 15 O， 18 F， 67 Ga， 111 In, 123 I和 201 TI等核医学用同位素，它的一个与众不同的特点是可同时引出二束束流，供同时生产的两种不同的放射性同位素之用。

• the classical cyclotron history of the cyclotron, basic concepts and scalings, focusing, stepwidth, relativistic relations, classification of cyclotron-like accelerators • synchro-cyclotrons concept, synchronous phase, example • isochronous cyclotrons ( sector cyclotrons ) isochronous condition, focusing in Thomas-cyclotrons, spiral angle,

The characteristics of a spectrometric isochronous cyclotron for producing beams of protons, deuterons and other particles having a maximum energy of 80 MeV (for protons), average current 100 pA and energy spread 10-4 are

•An cyclotron is supposed to accelerate ions with A nucleons and a charge state Q. •Demonstrate that the maximal kinetic energy E/ A of a cyclotron is E/ A = Kb. (Q/A)2 Nota : Give the Kb factor in a non relativistic approximation using the extraction radius R, …

Uses same decreasing field with radius as classical cyclotron ISOCHRONOUS: raise the magnetic field with radius such that the relativistic mass increase is just cancelled

Yet another solution: the isochronous cyclotron •Two contributions to vertical focusing: –vq B r => obtained in the radially decreasing rotationally symmetric magnetic fields as in the classical cyclotron and the synchro-cyclotron –v r Bq => requires an azimuthal modulation of the magnetic field => introduce sectors (hills) with high ...

In this cyclotron a spatially varying magnetic field provides for both focusing and isochronous orbits. This azimuthally varying field has three-fold symmetry and gives an estimated maximum energy of 75 MeV for protons, 100 MeV for N 4+ .