Recently, we are given task about particle beam therapy in cyclotron.
HISTORY OF CYCLOTRON
In 1932, Ernest O. Lawrence invented cyclotron which is a type of particle accelerator in which charged particle accelerate outwards from the centre 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.
Cyclotrons were the most powerful particle accelerator technology until the 1950s when they were superseded by the synchrotron, and are still used to produce particle beams in physics and nuclear medicine.
l The largest single-magnet cyclotron was the 4.67 m (184 in) synchrocyclotron ( 1940 & 1946 ) by which could accelerate protons to 730 MeV.
l The largest cyclotron is the 17.1 m (56 ft) multimagnet TRIUMF accelerator at the University of British Columbia in Vancouver, British Columbia which can produce 500 MeV protons.
THE PRINCIPLE OF OPERATION FOR CYCLOTRON
Alternating voltage which is applied between two hollow "D"-shaped sheet metal electrodes called "dees" inside a vacuum chamber.
The dees are placed face to face with a narrow gap between them, creating a cylindrical space within them for the particles to move.
The particles are injected into the center of this space. The dees are located between the poles of a large electromagnet
The magnetic field from dees causes the particles path to bend in a circle due to the Lorentz force perpendicular to their direction of motion.
Magnetic field would travel in a circular path within the dees under the influence of the magnetic field if speed is constant.
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