Presentation is loading. Please wait.

Presentation is loading. Please wait.

Particle Accelerators

Similar presentations


Presentation on theme: "Particle Accelerators"— Presentation transcript:

1 Particle Accelerators
Designed to accelerate charged particles to higher energies . These high energy particles can then be smashed into a target to probe the nature of matter or the wave properties of the fast moving particles can be used to probe( electron microscope )

2 Principles of Accelerators
Regardless of whether the particle accelerator is linear or circular, the basic parts are the same: a source of particles (this may be another accelerator) beam pipes (a guide along which the particles will travel whilst being accelerated) accelerating structures (a method of accelerating the particles) a system of magnets (either electromagnets or superconducting magnets as in the LHC) a target (in the LHC the target is a packet of particles travelling in the opposite direction). LHC Large Hadron Collider

3 Electric Fields A charged particle inside an Electric field experiences a force. The field does work on the charged particle. The electric work is turned into kinetic energy work done = charge x potential difference W = Q x V = ½ mv2

4 Example -200V +300V a) Calculate the work done on the proton by the electric field. W = Q x V W = 1.6x10-19 x 500 W = 8.0x10-17 J proton Ek gained = work done on proton Ek = 8.0x10-17 = ½ mv2 2Ek = mv Ek/m =v2 b) Calculate the speed of the proton at the –ve plate if it was initially stationary

5 b) Calculate the speed of the proton at the –ve plate if it was initially stationary
Ek gained = work done on electron Ek = 8.0x10-17 = ½ mv2 2Ek = mv Ek/m =v2

6 Another unit for Energy
Particle Physicists measure energy in electronvolts, eV. 1eV is the energy gained by an electron when accelerated through a p.d. of 1V. 1eV = Q x V = 1.6 x10-19 x 1 = 1.6 x10-19eV To probe the nucleus we need particles in the GeV range

7 Electric Field patterns
The arrow shows the direction a free positive charge would accelerate in. The closer the lines the stronger the field. For a point –ve charge the arrows would point towards the charge

8 More field patterns An +ve and –ve charge of equal magnitude
An +ve and –ve charge of equal magnitude ( similar to the magnetic field around a bar magnet )

9 And more patterns 2 equal charges. Null point between them, no force is experienced here. Field is uniform for parallel plates. https://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Field_lines_parallel_plates.svg/524px-Field_lines_parallel_plates.svg.png

10 Magnetic Fields A moving charge has a magnetic field about it. This can interact with another magnetic field . The direction of the charged particle can be controlled. The magnetic field does no net work on the charged particle, its speed remains constant.

11 Field pattern around a moving charge
© Douglas Morrison direction of electron flow Left hand grip rule. The thumb points in the direction of the North Pole,

12 Movement of charged particles
Right Hand Motor Rule : Hold the thumb and first 2 fingers at 900 to each other. Thumb ; direction of motion 1st finger : points North to South 2nd finger : points direction of current


Download ppt "Particle Accelerators"

Similar presentations


Ads by Google