Temporally Resolved Langmuir Probe Measurements in LAPPS

Electron beams efficiently ionize and dissociate gas, to form low temperature (<1.5 eV) high-density (1O(to the 10)-lO(to the 12)cm(to the -3) plasmas with low internal fields. These plasma sources have culminated in LAPPS, NRL's Large Area Plasma Processing System for surface modification of materials. Single Langmuir probes were constructed and used to determine global plasma parameters (electron temperature, density, and plasma potential) in modulated plasmas generated by high-energy (2 keV) electron beams. This work describes in detail the construction of probes, applications of probes in modulated systems and magnetic fields, data acquisition, and data analysis used in the study of electron beam generated plasmas.