Identification of the Ionic Species in a Cesium Plasma Diode

Abstract

The identification of the dominant ionic species in the cesium plasma diode has been established experimentally as the atomic ion, Cs+, instead of the molecular ion, C82+. Values of the atomic ion density, Ni, have been determined spectrographically by measurements of the radiative recombination spectrum leading to the 6P state. Electron densities, Nt, were measured independently by the Stark broadening of selected cesium lines. Within experimental uncertainty for a broad range of diode operating conditions, N.=N •. Thus, not only are Cs+ ions directly observed, but any important concentrations of Cs 2 + would violate plasma neutrality. The experimental results are consistent with the existence of local thermodynamic equilibrium.

A Technique for Time-Resolved Imaging of Millimeter Waves Based on Visible Continuum Radiation from a Cs-Xe DC Discharge — Fundamentals and Applications

“…It was shown that the electron-Xe atom bremsstrahlung continuum (e-Xe BC) and the cesium recombination continuum (RC) give the main contributions to the visible continuum radiation from the PC of a Cs-Xe discharge. The VC emission coefficient ξ(λ) is equal to the sum of emission coefficients for the electron-Xe atom bremsstrahlung continuum ξ e−Xe BC (λ) [39][40][41][48][49][50] and the cesium recombination continuum ξ RC (λ) [39,51]:…”

“…Visible RC radiation originates from recombination of the electrons and Cs + ions into 6Р and 5D electronic states of cesium (blue and yellow cesium RC, respectively) [51]. Thus, the emission coefficient for the recombination continuum of cesium in the visible region is equal to ξ RC (λ) = ξ 6P…”

“…RC (λ), where ξ 6P RC (λ) and ξ 5D RC (λ) are the emission coefficients for 6P-and 5D-recombination continua of cesium, respectively. The emission coefficients of the blue and yellow cesium recombination continua for λ < hc / Ε n are equal to [27,39,51] ( ) (…”

Microwave beams imaging by recombination continuum of cesium emitted by the positive column of the Cs-Xe DC discharge

“…In this paper, we discuss the method of microwave beam imaging by the blue recombination continuum of cesium emitted by a slab of the positive column (PC) of a Cs-Xe dc discharge. The blue recombination continuum of cesium (optical wavelength shorter than 500 nm) originates from radiative recombination of electrons and cesium atomic ions into the 6P state of cesium [3]- [5]. We anticipate that this sensitive imaging method can be used for real-time recording of the spatial distribution of microwave intensity.…”

“…This filter set transmitted about (40 10)% of light in the region of 400-500 nm and less than 0.1%, beyond that range. It transmitted also less than 0.1% of light in the range of 450-460 nm, where the lines of the second resonance doublet of cesium (7P 6S) occur [5]. The best temporal resolution was 1 ms, which was limited by the value of minimum illumination of the CCD camera KC-381.…”