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Contents 1 Particle Accelerators 2 The Basis of all Particle Accelerators 2.1 Particle Production 2.2 Particle Acceleration 2.3 Particle Guidance 2.4 Particle Containment

Particle Accelerators

The Basis of all Particle Accelerators

Particle accelerators consist of 4 main parts:

1. Particle production
2. Particle acceleration
3. Particle guidance
4. Particle containment

These parts are common to all systems – only the design and form of the system changes.

Particle Production

• Particle production depends on the particles used in the accelerator.
• At its simplest, this could be a hot wire producing electrons via thermionic emission.
• More complicated systems involve the use of radioactive sources or particle collisions from other particle accelerators to produce the particles.
• One feature common is the use of charged particles.

Particle Acceleration

• The section of the accelerator which increases the energy of the charged particles.
• This usually uses potential difference to accelerate the charged particle.
• The energy increase is equal to eV (where e is the charge of the particle, and V is the accelerating potential difference) and results in an increase in the kinetic energy of the particles.
• Usually the particles are accelerated multiple times.
• but the speed canot be increased indefinitely, because when the speed increases mass of the particle also increases.

Particle Guidance

• Depending on the design of the accelerator, the charged particles may need to travel in a straight or curved path. If a curved path is required, the particles are deflected by a magnetic field – magnetic fields are chosen because they cause the particles to travel in a predictable circular path, which is easily modelled.

Particle Containment

• Groups of similarly charged particles tend to separate from each other and hence need to be contained into a tight packed or beam.
• To do this, magnetic fields are often used as a containment field.
• This also helps to keep the particles away from the walls of the containment vessel and so stop them interacting with their surroundings.
• The containment vessel is evacuated in order to stop interactions with air.