Plasma energy balance in the L-2M stellarator

Results are presented from studies of the effect of the discharge parameters (in particular, plasma density and heating power) and the characteristics of the magnetic configuration (e.g., rotational transform) on the confinement of a low-pressure plasma during electron-cyclotron resonance heating in the L-2M stellarator. An analysis shows that the plasma energy in the steady-state phase of a discharge is fairly well described by the product of power functions of the plasma density, heating power, and rotational transform: W = W₀ nₑα ₙ Pα ₚ ι α _ι . The energy scalings constructed in terms of the parameters in the initial stage of free plasma decay and those in the steady-state phase are close to one another. The dynamic analysis of the plasma energy decay is now under way.