Runaway Electrons

Electrons accelerated to high energy during disruptions that can damage the wall.

In a disrupting plasma, electric fields can accelerate a beam of electrons to tens of MeV. Uncontrolled, this runaway beam can damage the wall, so disruption mitigation aims to avoid or dissipate it.

During a disruption's current quench, electric fields can accelerate a beam of electrons to tens of MeV that, uncontrolled, would gouge the wall. Preventing or dissipating this beam is a core part of disruption mitigation on any tokamak — and a problem the disruption-free burner does not have.