Particle accelerators

• Linear particle accelerators consist of a series of tubes of increasing length, with the particle being accelerated by the potential difference (p.d) between a pair of tubes.
• The potential difference alternates, causing the particle to reverse its polarity, changing from positive to negative or negative to positive, to ensure the particle keeps accelerating.
• The tubes in a linear particle accelerator get longer as the speed of the particles increase, meaning the frequency of the alternating p.d is constant.
• In a cyclotron, a uniform magnetic field provides a centripetal force, making the particles move along a circular path.
• The equation for the acceleration of a particle in a cyclotron is Bqv=rmv2.
• The frequency for the alternating p.d in a cyclotron can be calculated using the equation f=2πmBq.
• In a synchrotron, particles are accelerated, and their path kept circular, by increasing the strength of the magnetic field as the speed of the particles increases.
• As the speed of the particles increases, the time it takes the particle to travel through each tube decreases, meaning the frequency of the alternating p.d must also increase.
• At any point in time, the particle in a synchrotron will experience a centripetal force due to the magnetic field.
• The equation for the acceleration of a particle in a synchrotron is Bqv=rmv2.
• The frequency for the alternating p.d in a synchrotron can be calculated using the equation f=2πmBq.