Runaway Ions Research Articles

Possibility of Ion Runaway in Zeta

BS>Investigations indicate that runaway ions cannot occur in the conditions which apply on the average in Zeta. It is possible that ion runaway'' occurs in restricted regions of the discharge where conditions are abnormal. Examples of such regions are: regions where the electron velocity is limited by other means than collisions with the deuterons; regions of low electron temperature into which particles may be injected, from other parts of the plasma, with sufficient energy to satisfy the relationship W/sub i//W/sub e/ > 1.6 (where W/sub 1/is the velocity of a singly charged ion and W/sub e/ is the mean thermal velocity of the electrons); and regions largely occupied by runelectron streams, where ion-electron collisions are unimportant. There is as yet insufficient evidence to show whether or not any such regions exist. (J.H.M.)