beam

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schematic diagram of a synchrotron with alternating-gradient focusing

beam

physics

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June 22, 2026

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schematic diagram of a synchrotron with alternating-gradient focusing — schematic diagram of a synchrotron with alternating-gradient focusing Particles are injected into the synchrotron ring (shown at top) with their energies already raised by a linear accelerator. They are further accelerated around the synchrotron by a series of electromagnets, whose applied fields grow stronger as the speed of the particles rises. The beam of particles is focused by the pole-tips of the magnets, shown in cross section at bottom. Tips with cross section cd focus the beam in the radial direction, while tips with cross section ab focus in the vertical direction.

In physics, a beam refers to a stream of particles or waves moving in the same general direction, often within a vacuum. This can include beams of light, such as from a flashlight or laser, or beams of subatomic particles like electrons or protons used in particle accelerators. Magnetic fields are crucial for controlling and focusing these particle beams, guiding them along specific paths. In particle physics research, beams are often made to collide to study their interactions. Neutron beams, extracted from nuclear reactors or accelerators, are also used for scientific study. In engineering, a beam is a structural element, typically horizontal, that supports a load.12345678

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particle accelerator
Classical cyclotrons
The beam current in a classical cyclotron operated at high voltages can be as high as five milliamperes; intensities of this magnitude are very useful in the synthesis of radioisotopes.
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The beam current in a classical cyclotron operated at high voltages can be as high as five milliamperes; intensities of this magnitude are very useful in the synthesis of radioisotopes.
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particle accelerator
Proton storage rings
The creation of an intense beam of antiprotons requires a technique known as “stochastic cooling,” developed by Simon Van der Meer at CERN. Antiprotons are produced when a high-energy proton beam strikes a metal target, but they emerge from the target with a range of energies and directions, so the…
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The creation of an intense beam of antiprotons requires a technique known as “stochastic cooling,” developed by Simon Van der Meer at CERN. Antiprotons are produced when a high-energy proton beam strikes a metal target, but they emerge from the target with a range of energies and directions, so the…
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particle accelerator
Sector-focused cyclotrons
…the synchrocyclotron is that the beam is not pulsed and is more intense. The frequency of the accelerating voltage is constant, and the orbital frequency of the particles is kept constant as they are accelerated by causing the average magnetic field on the orbit to increase with orbit radius. This…
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…the synchrocyclotron is that the beam is not pulsed and is more intense. The frequency of the accelerating voltage is constant, and the orbital frequency of the particles is kept constant as they are accelerated by causing the average magnetic field on the orbit to increase with orbit radius. This…
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particle accelerator
Synchrocyclotrons
…confers stability on the entire beam and makes it possible to accelerate the particles uniformly, by modulating the frequency, without dispersing them. The small periodic variations of the particles about the equilibrium values of phase and energy are called synchrotron oscillations.
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…confers stability on the entire beam and makes it possible to accelerate the particles uniformly, by modulating the frequency, without dispersing them. The small periodic variations of the particles about the equilibrium values of phase and energy are called synchrotron oscillations.
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particle accelerator
Synchrotrons
…accelerating voltage, and very intense beams can be produced.
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…accelerating voltage, and very intense beams can be produced.
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particle accelerator
Van de Graaff generators
These devices provide a beam with twice the energy that could be achieved by one application of the high voltage. For the first stage of a tandem accelerator, an ion source yields a beam of protons, which are accelerated to a low energy by an auxiliary high-voltage supply. This…
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These devices provide a beam with twice the energy that could be achieved by one application of the high voltage. For the first stage of a tandem accelerator, an ion source yields a beam of protons, which are accelerated to a low energy by an auxiliary high-voltage supply. This…
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particle accelerator
Linear electron accelerators
…not survive continuous service), the beams from these accelerators are delivered in short bursts.
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…not survive continuous service), the beams from these accelerators are delivered in short bursts.
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