Volume 92, Issue 3, 01 August 2002
Index of content:
- PLASMAS AND ELECTRICAL DISCHARGES (PACS 51-52)
92(2002); http://dx.doi.org/10.1063/1.1490156View Description Hide Description
Oscillations stimulated by an S-shaped negative differential resistance originating from the self-assembly and decay of a self-organized space charge configuration in front of the anode of a dc gas discharge were observed. The oscillations appear in a resonant circuit, appropriate for the discharge, which contains a capacitor having a plate charged by secondary electron emission. The plate can be a metallic or a dielectric one because the negative differential resistance operates at zero dc current to the plate.
92(2002); http://dx.doi.org/10.1063/1.1491592View Description Hide Description
Calculations for electron deposition in electron beamgenerated KrF laser at atmospheric pressure have been performed. The impact of the gas mixture on the electron energy distribution function, electron density, and mean energy,energy per electron–ion pair, attachment, dissociation, excitation, and ionization rates have been investigated. The abundance controls the low energy (≲9 eV) component of the distribution function, while both the fluorine and krypton mole fraction affect the distribution in the midenergy domain (9 to ∼25 eV). Consequently, the attachment rate coefficient varies with the mole fraction such that the electron density scales as The rate coefficient for direct dissociation of is smaller than for attachment but the former contributes more to the total power dissipation (∼8% at The excitation-to-ionization ratio for Kr is not constant, as generally assumed, but increases by a factor of two with a decrease in either the Kr or abundance. Combining the former and present investigations leads to a set of fitting formulas to be used in beam kinetics codes for various collision rates as a function of both the electron beam power density and the composition.