# variable energy in cyclotron centre

## variable energy in cyclotron centre

The cyclotron consist of two hollow semi-circular metal boxes D1 and D2 called ‘Dees’ as shown in figure variable energy in cyclotron centre

A source of ion is located near the middle point of the gap between the ‘Dees’ the Dees are insulated from to each other and are enclosed in another vacuum chamber the Dees are connected to a powerful radio frequency oscillator the hole operator is placed between the pole piece of astrong electromagnet the magnetic field is perpendicular to the plane of the Dees

## Theory of working

Suppose the positive ion leave the ion source at the centre of the chamber at the instant the D1 and D2 are at the maximum negative and positive AC potential respectively the positive ion will be accelerated towards the negative Dees D1 before entering it the ion enter the space inside the Dees with a velocity ‘v’
where ‘v’ is applied voltage and ‘e’ and ‘m’ are the charge and mass of the ion respectively when the ion is inside the Dees it is not accelerated since the space is field free inside the Dees, under the action of applied magnetic field the ion traveled in electron circular path of radius ‘r’
suppose the strength of the field (B) or of the frequency of oscillation are so adjusted that by the time the ion has described a semi-circular path and just enters the space between D1 and D2 has become negative with respect to D1 the ion is the accelerated towards D2 and enter the space inside it with a grater velocity since the ion is now moving with greater with it will describe a semi-circular of grater radius in the second Dees
The time taken by the ion to describe a semicircular is independent of both the radius ‘D’ the path (r) and the velocity of the ion ‘v’ hence the ion describe all semicircular whatever be there radii in exactly the same time this process continue until the ion nucleus periphery of the Dees the ion thus spiral round in circle of increasing radius and acquired high energy the ion will finally comes out of the Dees in the direction indicated through the window