Cyclotron presentation

charge accelerator is actually called cyclotron

1. Cyclotron Group Members : Sahib Ullah (BEE-F14-207) Faisal Khan (BEE-F14-291) Zain Aslam (BEE-F14-270)

2. layout Introduction to cyclotron. Principles. Construction. Diagram Working of cyclotron. Calculations. Applications. Limitations. Advantages.

3. cyclotron A cyclotron is a device used to accelerate charged particles to high energies without use of high voltage It is a circular particle accelerator capable of generating particle energies between a 1 MeV to more than 100 MeV Accelerate charged particles like protons, deuterons, etc. ions using electric and magnetic field

4. introduction The cyclotron was one of the earliest types of particle accelerators, and is still used as the first stage of some large multi-stage particle accelerators. One of the most interesting applications of motion of charge particles in electric and magnetic fields is Cyclotron. Cyclotrons produce very high energy Charge Particles, E.O Lawrence and M.S Livingston invented this machine in 1934 .  

5. principles This is a charged particle accelerating device. The motion of the charged particle under perpendicular magnetic field is only applied in the apparatus named cyclotron . Cyclotron works on the principle that a charged particle moving normal / perpendicular to a magnetic field experiences magnetic Lorentz force due to which the particle moves in a circular path. Lorentz’s Force is the basic principle of Cyclotron . Conceptually this device is very simple but it has huge uses in the field of engineering, physics and medicine .

6. construction This device basically has three main constructional parts: Large sized electromagnet to create uniform magnetic field in between its two face-to-face placed magnetic opposite poles . Two low height hollow half cylinders made of high conductive metals. These components of cyclotron are called Dees . A high-frequency alternating high voltage source.

7. Basic components of cyclotron Magnetic system. Ion source system. Dees. RF system. Extraction system. Vacuum system. Target assembly.

8. diagram

9. Working of cyclotron When a positive ion of charge q and mass m is emitted from the source, it is accelerated towards the Dee having a negative potential at that instant of time . Due to the normal magnetic field, the ion experiences magnetic L orentz force and moves in a circular path . By the time the ion arrives at the gap between the Dees, the polarity of the Dees gets reversed.   Hence the particle is once again accelerated and moves into the other Dee with a greater velocity along a circle of greater radius.

10. cont’d Thus the particle moves in a spiral path of increasing radius and when it comes near the edge, it is taken out with the help of a deflector plate (D.P ). The particle with high energy is now allowed to hit the target T . When the particle moves along a circle of radius r with a velocity v, the magnetic Lorentz force provides the necessary centripetal force . Bqv = v m 2/ r

11. Working Production of charge particle Acceleration of charge particle Extraction of beam Bombardment of target

12. calculations In magnetic field magnetic force acts as a centripetal force. Radius at each turn increase due to increase in velocity, therefor its behaves like Spiral. Now angular frequency, from equation above we get,  

13. Cont’d So the frequency is Now time period T, Frequency and Time period is independent of radius.    

14. Types of cyclotron On the basis of Ions Shielding Energy Direction

15. applications Best source of high-energy beams used for experiment in nuclear physics, where high energy collisions are required. Cyclotrons can be used in particle therapy to treat cancer. Cyclotron beams can be used to bombard other atoms to produce short-lived positron-emitting isotopes suitable for PET imaging  .

16. limitations Maintaining a uniform magnetic field over a large area of the Dees is difficult . At high velocities, relativistic variation of mass of the particle upsets the resonance condition. At high frequencies, relativistic variation of mass of the electron is appreciable and hence electrons cannot be accelerated by cyclotron.

17. cont’d It cannot accelerate neutron, because neutron do not have any charge. The energy of charged particles emerging from cyclotron, is limited due to variation of mass with velocity, i.e. Where is the rest mass, m is the mass in motion when velocity is v and c is the velocity of light.  

18. advantages Utilizes a single, electrical driver. This saves energy and $. High power due to continuous stream of particles. Compact design.