Floating potential of an electron emitting electrode in a two-electron temperature plasma

Formation of plasma potential in front of an electron emitting electrode (collector) immersed in a plasma with two electron populations is studied theoretically. The problem is treated by a static. kinetic plasma-sheath model of Schwager and Birdsall, L.A. Schwager and C. K. Birdsall, Phys. Fluids 132 (1990) 1057. It is assumed that four groups of charged particles axe present in the plasma: the singly charged positive ions, the cool electrons, the hot electrons and the secondary electrons emitted from the collector. The model is one dimensional. The velocity distribution functions of all 4 species of particles are assumed to be maxwellian with different temperatures and cutoff velocities. In this work we focus our attention on the dependence of the collector floating potential, plasma potential in the presheath region and critical emission coefficient on the density and temperature of the hot electrons.