Fundamentals of Multipaction - Lesson 2

Multipaction is an electron resonance effect that occurs when applied RF fields accelerate electrons that are in a vacuum and cause them to impact with a surface, which depending on the impact energy, releases one or more electrons into the vacuum, producing an avalanche effect, similar to what we see in lasers.
These electrons can then be accelerated by the RF fields and impact with the same or another surface. When the impact energies, number of electrons released and timing of the impacts are such that a sustained multiplication of the number of electrons occurs, the number of released electrons will grow exponentially. This may lead to operational problems that are not necessarily catastrophic right away, but they can build up over time to cause a catastrophic failure.

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