The plasma must be held and squeezed by an invisible magnetic bottle and never allowed to touch any material object, including the walls of the chamber; the least contact with any matter instantly cools the plasma and prevents it from maintaining fusion conditions.
22.
So it sounds to me like the whole " magnetic bottle " metaphor mentioned in the article I linked to above is a lot more accurate than " magnetic mirror . " Since what it sounds like you're really doing is using a set of magnetic fields to keep high-energy / high-velocity particles curving around and around within the " bottle, " thus containing them.