Helium oscillations in burning tokamaks

Thermonuclear alpha particles transfer their energy by slowing down on the electrons and ions of bulk plasma, after which time the alpha particles bec ome helium ash, which dilutes the plasma and reduces the fusion rate. The h elium ash is shown to cause temperature oscillations that are unacceptable for reactor performance, but as an example, an ITER-like plasma is used to demonstrate that these oscillations can be controlled effectively by modula ting auxiliary power.