Cyclotron

Cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1932 in which charged particles accelerate outwards from the center along a spiral path. The particles are held to a spiral trajectory by a static magnetic field and accelerated by a rapidly varying (radio frequency) electric field.

History

The cyclotron was invented and patented by Ernest O. Lawrence of the University of California, Berkeley, where it was first operated in 1932. With Stanley Livingston as his graduate student, Lawrence constructed the first cyclotron at Berkeley. Livingston went on to head the project when Lawrence moved on to other projects.

Operation

In a cyclotron, a high-frequency alternating voltage applied across the "D" electrodes (also called "dees") alternately attracts and repels charged particles. The particles, injected near the center of the magnetic field, increase in speed and move in larger and larger orbits until they hit a target at the perimeter of the vacuum chamber, or leave the cyclotron through an exit port.

Applications

Cyclotrons have many practical applications. In medicine, cyclotrons often produce radioisotopes for radiopharmaceuticals that are used in PET scans. Cyclotrons can also be used in particle therapy to treat cancer, where the particles are used to bombard diseased tissue.

See also

• Synchrocyclotron
• Magnetic field
• Particle accelerator
• Ernest O. Lawrence
• Stanley Livingston

References

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  Cyclotron with glowing beam
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  4-inch cyclotron
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  Berkeley 60-inch cyclotron
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  Cyclotron diagram
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  Cyclotron patent
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  Lawrence 27 inch cyclotron dees 1935
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  Spiral fermat 1
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  Lorentz factor
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  1937 French cyclotron
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  Cyclotron - University of Washington
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  M. Stanley Livingston (L) and Ernest O. Lawrence in front of 27-inch cyclotron at the old Radiation Laboratory