Electron density and two-channel neutron emission measurements in steady-state spherical inertial-electrostatically confined plasmas, with review of the one-dimensional kinetic model

Abstract

Electron density measurements have been made in steady-state plasmas in a spherical inertial electrostatic confinement (IEC) discharge using microwave interferometry. Plasma cores interior to two cathodes, having diameters of 15 and 23 cm, respectively, were probed over a transverse range of 10 cm with a spatial resolution of about 1.4 cm for buffer gas pressures from 0.2 to 6 Pa in argon and deuterium. The transverse profiles are generally flat, in some cases with eccentric symmetric minima, and give mean densities of from ≈0.4 to 7×1010 cm−3, the density generally increasing with the neutral gas pressure. Numerical solutions of the one-dimensional Poisson equation for IEC plasmas are reviewed and energy distribution functions are identified which give flat transverse profiles. These functions are used with the plasma approximation to obtain solutions which also give densities consistent with the measurements, and a double potential well solution is obtained which has minima qualitatively similar to those observed. Explicit consideration is given to the compatibility of the solutions interior and exterior to the cathode, and to grid transparency. Deuterium fusion neutron emission rates were also measured and found to be isotropic, to within the measurement error, over two simultaneous directions. Anisotropy was observed in residual emissions during operation with nonfusing hydrogen-1. The deuterium rates are consistent with predictions from the model. 2004 American Institute of Physics.

Measurement and modeling of a diamond deposition reactor: Hydrogen atom and electron number densities in an Ar∕H2 arc jet discharge

“…We first describe how these densities are extracted from experimental spectra, and then discuss the limitations of the data inversion and how quantitative comparisons with the model predictions are best made. The elec- tron density is an important plasma parameter, but precise measurements are challenging: under conditions of high electron density, interferometric methods 39 or Thomson scattering 11,40 can be used. At the relatively low electron densities of the arc jet reactor plume, however, we instead retrieve electron densities from the Stark broadening of atomic absorption lines.…”

A Comprehensive Overview of Research Groups and Activities in the Field of Inertial Electrostatic Confinement Fusion

“…For example, Hirsch's six-gun ion experiment was moved from the labs of ITT Farnsworth Research Corporation to the Brigham Young University [42]. Similarly, one device from the University of Illinois was temporarily moved to the Marshall Space Center [4], [43].…”

Prediction of Neutron Yield of IR-IECF Facility in High Voltages Using Artificial Neural Network

“…Therefore IECF is considered as a source of hot and dense plasma, highly energetic ions, and fast neutrons (when using deuterium or mixture of deuterium-tritium gas). IECF device is an excellent apparatus because of its ability to generate fast neutrons with high-flux from a small source for many applications, such as medicine (e.g., boron neutron capture cancer therapy) [1][2][3], radiography or tomography of thick materials, space propulsion system [4], inspection system and explosive landmine detection [5], neutron activation analysis, mine and petroleum exploration, and security screening. Therefore neutron production rate optimization in this device will increase its efficiency for the above applications.…”

“…IEC researches have been performed since the 1950s decade. Recently, over the last 10 years, many researches and developments on IECF neutron source have been done [2,4,[6][7][8]. Most of these developments are created by the usage of the different ion sources and enhancement of voltage and current [2,4,6].…”

“…Recently, over the last 10 years, many researches and developments on IECF neutron source have been done [2,4,[6][7][8]. Most of these developments are created by the usage of the different ion sources and enhancement of voltage and current [2,4,6]. IR-IECF is the prototype IEC device that is structured at the Atomic Energy Organization of Iran (AEOI) and the preliminary experiments on neutron yield were performed [7].…”