Session 7P - Plasma Applications and Plasma Technology.
POSTER session, Thursday morning, November 14
Exhibit Hall - Concourse Level, Adam's Mark
Spin functions for three electrons have two distinct s = \frac12 doublets. We apply these two doublets to the plasma in the cold region of the sheet plasma type negative ion source. If liberated electrons have proper energies, the degenerate two ground states are considered to be in a kind of equilibrium; \[ e + e + H \leftrightarrow e + H^- \;\;. \] Then, we obtain the following one dimensional Saha equation.^1 \[ n_e^1/3 \fracn_0n^- = \frac4\lambda \exp \left( - \frac\epsilon - eV_sT_e \right) \] where \lambda [cm] = \frach\sqrt2 \pi m T_e = 6.94 \times 10^-8 \frac1\sqrtT_e [eV], and \frac1n_e^1/3 = \int dx, V_s is the plasma potential, \epsilon is the electron affinity, h is the plank constant, n_0 is the density of H atom and n^- is the density of H^- ion. In the sheet plasma experiment, a relation between negative hydrogen ion currents and plasma potentials is well explained by this equation. 1. K. Jimbo: J. Phys. Soc. Jpn. 65, to be published (1996).