Cryopump

A pump that captures gas by freezing it on cold surfaces.

A cryopump condenses or adsorbs gas on very cold surfaces, achieving the high pumping speeds and ultra-high vacuum a plasma needs. It is the workhorse of fusion vacuum systems.

Cryopumps freeze exhaust gas onto very cold surfaces, achieving the high pumping speeds a fusion vessel needs to control density and remove helium ash. They fill up and are periodically regenerated, and on the breeder that regeneration is part of the tritium-handling loop.