Microtron
A microtron is a type of particle accelerator concept originating from the cyclotron in which the accelerating field is not applied through large D-shaped electrodes, but through a linear accelerator structure. The classic microtron was invented by Vladimir Veksler. 
The kinetic energy of the particles is increased by a constant amount per field change (one half or a whole revolution). Microtrons are designed to operate at constant field frequency and magnetic field in the ultrarelativistic limit. Thus they are especially suited for very light elementary particles, namely electrons.

In a microtron, due to the electrons' increasing momentum, the particle paths are different for each pass. The time needed for that is proportional to the pass number. The slow electrons need one electric field oscillation, the faster electrons need an integer multiple of this oscillation.
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particle accelerator
Concept
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cyclotron
Concept
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linear accelerator
Concept
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Vladimir Veksler
PER
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frequency
Concept
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magnetic field
Concept
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ultrarelativistic limit
UNK
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electrons
Concept
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Microtron
Concept
discoverer or inventor
subclass of