(Science: radiobiology) component of a toroidal fusion device that diverts charged particles on the outer edge of the plasma into a separate chamber where they strike a barrier and become neutralised. In a reactor, the divertor would incorporate a system for pumping out the neutralised particles as exhaust from the machine. A divertor, like a limiter, prevents the particles from striking and degrading the chamber walls and dislodging secondary particles that would cool and contaminate the plasma. Whereas a limiter is a material object used to limit the shape of the plasma, a divertor is a magnetic-field construction. The advantage of the divertor is that it allows the neutralisation region to be removed from the main plasma.