METHOD OF CONTROL OVER CURRENT OF PLASMA EMITTER OF LARGE AREA Russian patent published in 1994 - IPC

FIELD: experimental physics, electron and ion sources with plasma emitters. SUBSTANCE: invention may also find in acceleration equipment. For control over current of plasma emitter of large area potential of emission electrode is set equal to potential of emitting plasma. With stable concentration of plasma of auxiliary discharge difference of potentials between plasma of auxiliary discharge and electrode separating this plasma from emitting plasma change within intervals from 4,3·10^-5·T_e·ln(Π/2·m_c/M_i) to 8,8×10^-8·n2/3aux

·T1e^/3·r^4/3, where T_e and n_aux are temperature and concentration of emitrons of plasma of auxiliary discharge accordingly; m_e and M_i are correspondingly masses of electron and ion of plasma forming gas; r is radius of hole in electrode separating plasma of auxiliary discharge from emitting plasma. Setting of potential of emission electrode equal to potential of emitting plasma removes potential barrier for electrons close to this electrode acting on energy efficiency of emitter and homogeneity of emission from peripheral sections of emitter and control over emission current I_e of plasma emitter accompanied by reduction of power used to generate I_e is performed by adjustment of value of flux of electrons injected from auxiliary discharge into expander under change of difference of potentials between plasma of auxiliary discharge and electrode which separates this plasma from emitting plasma. with change of difference of potentials within specified limits length of ion layer close to wall of hole in separating electrode alters which makes it possible to control area of plasma of auxiliary discharge from which selection of electrons injected into expander takes place from its maximum value to zero. EFFECT: improved reliability of control. 1 dwg