P-4, A STEADY-STATE PLASMA SYSTEM

摘要

The reasons for drawing Vs nearly flat in the region r ≤ 1/2 cm come from a consideration of the electrons with energies greater than about 25 ev. These fast electrons originate mainly in the arc discharge region and are principally fed, directly or indirectly, by thermionic emission from the end cathode which is about 1 50 volts below plasma potential. In the downstream plasma column most of the fast electrons will be found within the same mag¬netic flux tube that encloses the plasma in the discharge region, since these electrons are removed from the fast electron class by inelastic collisions be¬fore they have much chance to diffuse outward.