cyclotron frequency

physics

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June 25, 2026

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The cyclotron frequency refers to the fixed frequency at which charged particles orbit within a cyclotron, a type of particle accelerator. This frequency is determined by the strength of the magnetic field and the mass of the particles, not their speed, as long as their speed is significantly less than the speed of light.12

A cyclotron uses a constant magnetic field to guide particles in a circular path while an alternating electric field accelerates them each time they cross a gap between two electrodes called "dees". This process causes the particles to spiral outwards with increasing energy. However, as particles approach the speed of light, their mass increases due to relativistic effects, causing their orbital frequency to decrease and limiting their maximum energy. Devices like synchrocyclotrons and isochronous cyclotrons were developed to overcome this limitation by varying the electric field frequency or magnetic field strength.123

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electron tube
Electron motion in a vacuum
…at a rate called the cyclotron frequency, ω_c, given by e/mB. The circle traced out by the electron has a radius equal to mv/eB. This circular motion is exploited in many electron devices for generating or amplifying radio-frequency (RF) power.
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…at a rate called the cyclotron frequency, ω_c, given by e/mB. The circle traced out by the electron has a radius equal to mv/eB. This circular motion is exploited in many electron devices for generating or amplifying radio-frequency (RF) power.
Read More

mass spectrometry
Ion-trap methods
Both make use of the cyclotron principle (see particle accelerator: Cyclotrons), in which positive ions produced by a beam of electrons flowing along the axis of a uniform magnetic field follow circular trajectories with a radius proportional to momentum, r = mv/zB, and a frequency of rotation inversely proportional to…
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Both make use of the cyclotron principle (see particle accelerator: Cyclotrons), in which positive ions produced by a beam of electrons flowing along the axis of a uniform magnetic field follow circular trajectories with a radius proportional to momentum, r = mv/zB, and a frequency of rotation inversely proportional to…
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radio-frequency heating
Induction heating.
…that their frequency equals the cyclotron frequency of the plasma ions—i.e., the rate at which the ions travel around the doughnut-shaped magnetic field of a cyclotron (q.v.). Approximately 600 kilowatts of radio-frequency energy were utilized to heat the plasma to roughly 23,000,000 K.
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…that their frequency equals the cyclotron frequency of the plasma ions—i.e., the rate at which the ions travel around the doughnut-shaped magnetic field of a cyclotron (q.v.). Approximately 600 kilowatts of radio-frequency energy were utilized to heat the plasma to roughly 23,000,000 K.
Read More