Stabilization of flute instability in a dilute plasma by an uncompensated space charge

The author solves numerically the problem of using an uncompensated space charge to stabilize the flute instability in a dilute plasma (, where ωpi and Ωi are the ion plasma and ion cyclotron frequencies, respectively). For typical devices, this condition is fulfilled when the plasma density n < 1010 cm−3. It is shown that, if the space charge is sufficiently high, the flute instability is completely stabilized. The critical plasma decompensation (ni0 – ne0)/ne0) needed to stabilize different oscillation modes and the dependence of that critical value on plasma density, the ion Larmor radius and the plasma-to-wall gap are established.