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ProBeam Cyclotron


What is a Cyclotron?

A cyclotron is a compact particle accelerator that uses electromagnetic waves to accelerate particles. A stream of charged particles is fed into the center of the chamber, and voltage alternately attracts and repels the particles, causing them to accelerate.

Cyclotron Functionality

Cyclotron Functionality

A cyclotron uses a constant magnetic field and a constant frequency electric field in order to accelerate particles. As the particles—in this case, protons—are accelerated, they move in a spiral path. Each time the particles complete a lap, their speed increases, even approaching the speed of light. A cyclotron is capable of accelerating to high energies without requiring large voltages.

Compared to a synchrotron, a cyclotron has a constant rather than pulsed beam, as well as a smaller size and footprint, which may be an important consideration for a facility. The majority of accelerators used in proton therapy today are cyclotrons.

ProBeam Cyclotron Isochronous

ProBeam Superconducting Cyclotron

Varian's ProBeam® isochronous (particles taking the same time for each revolution) superconducting cyclotron is based on a well-established clinical design. Varian products have been used to treat patients with pencil beam scanning since 2007. With its continuous and stable proton beam, the beam intensity can be quickly modulated for advanced treatment delivery.


DGMP Annual Meeting
Stuttgart, Germany
EANO 2019
Lyon, France
COMP Annual Meeting
Kelowna, BC