Cyclotron basics and its operations

Cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1930 at the University of California, Berkeley and patented in 1932. Lawrence was awarded the 1939 Nobel Prize in Physics for this invention. It is based on a combination of RF acceleration and bending of charged particles in a magnetic field. This way the same electrode is used over and over again to give acceleration to the particles. In most of the modern medical cyclotrons there are four gaps with four pie shaped dees instead of two. The particles pass through the same acceleration gap many times with increasing radius before they acquire the desired energy. The entire accelerating system is maintained at high vacuum (10^-6 to– 10^-8 Torr) and the dees are housed in a vacuum chamber. Hydrogen gas is passed through an arc current to produce the ion source for acceleration in the cyclotron. The ion source is pulled towards the centre of dee structure by applying a positive bias voltage