Introducing
Your new presentation assistant.
Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.
Trending searches
Linear accelerator and Cyclotron
55
Linear Accelerators and Cyclotrons
Linear accelerator and Cyclotron
Particle accelerators
Charged particles such as electrons or protons are accelerated by an electric field to speeds almost equal to the speed of light. They are made to collide with one another and in such collisions some of the kinetic energy is turned into matter - new particles are created.
The simplest particle accelerator is the electron gun. The electrons are produced by heating a cathode. the electrons 'boil off' from the cathode and are accelerated toward an anode with a small hole in it. Many electrons pass through the hole forming an electron ray (cathode ray). There are two designs of particle accelerators used for producing particles of higher energy for research purposes - The linear accelerator and cyclotron.
Linear accelerator
Cyclotrons
often dubbed 'linac', a linear partical accelerates particles, increasing their kinetic energy by subjecting them to a series of oscillating electric potentials along a linear beam line ( A beam line refers to the particles trajectory).
The particles are accelerated in a straight line. An alternating potential difference is connected across adjacent cylindrical electrode tubes. charged particles are accelerated across the gaps between electrodes. by the time the particle reaches the next gap the polarity of electric field has reversed and so the particle is accelerated once more.
Linacs have advantages over cyclotrons, in that when a charged particle is moved in a circular path it radiates energy so a lot of input energy is wasted. this does not occur in a linear accelerator. However, the length of a linac limits the amount of energy achieved.
The length limitation can be overcome by making the charged particles follow a circular path. In a cyclotron the particles are accelerated across the gap between two 'D' shaped electrodes.
The radius of the circle increases after each successive acceleration, so the path spirals out from the source at the centre to the target on the outside.
The relatively small size of cyclotrons makes them useful for producing energetic particles for medical treatments and testing advanced industrial materials. As the speed of the particles approaches that of light, however, the relativistic mass increase becomes significant and this results in charges arriving too late to be accelerated across the gap. Therefore there is a limit of about 1GeV on the energy achievable.
For a solution to this, join me next time when I will be writing about 'Synchotrons'.