Saha-Langmuir surface ionization relation.
Discrepancy between observed ion production rate in cesium thermionic converter and Saha-Langmuir equation prediction suggests locality of ion formation
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Discrepancy between observed ion production rate in cesium thermionic converter and Saha-Langmuir equation prediction suggests locality of ion formation
Sputtering yields, angular and energy distribution of atoms, and implanted ion distribution in cesium and mercury surface interactions
Large amplitude oscillations with frequencies corresponding to ion transit times in thermal cesium plasma diodes with parallel plane construction
Dependence of tungsten electrode work functions on positive ion sheaths between electrodes and cesium plasmas
Spherical powder and wire bundle tungsten ion sources for ionization of cesium vapor
Linear ion thrustor and cesium feed system for possible satellite control systems application
Electrostatic ion thrustor employing cesium on tungsten contact ionization for satellite attitude control and stationkeeping missions
Tungsten microspheres used to fabricate cesium ionizers having improved uniformity, pore character and ionization performance
Method for producing porous tungsten plates for ionizing cesium compounds for propulsion of ion engines
Ion production rate in cesium thermionic converter related to Saha-Langmuir surface ionization equation
Large area ion chambers for a high energy cosmic ray experiment, scintillating plastic fibers as light pipes for a cosmic ray hodoscope, and an evaluation of clad scintillating light pipes were considered.
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Thermionic work functions and electron emission S curves for contaminated copper surface in oxygen and cesium vapors, separate and mixed
The primary objective of these tests outlined in the Test Plan for this work [15] and described herein was to demonstrate the vitrification of ion exchange media for cesium removal, either alone or in combination with a representative Hanford HLW stream. This included one formulation with chabazite as the only waste component and two formulations containing direct-feed fully washed AY-102 HLW solids combined with either CST or chabazite. Feed processing characteristics, glass production rate, melter emissions, and feed carryover were determined for each of the three feed compositions. This was accomplished through VGF and DM100 melter system testing.
Multistrip cesium contact thrustors, integral focus life test engine and various integral focus ionizers
This work reports ion generation in a cesium thermionic converter as part of advanced-model thermionic converter development research. A microwave with frequency in the range between 1-2 GHz is used to externally pump a thermionic converter as part of our effort in the verification of Lam's theory. It is found that the motive peak as predicted in the theory disappears whenever microwave power is used to excite the cesium plasma of the converter. The electron temperature is effectively heated by the microwave and the experimental data agrees with theory in the low-power output region.
Neutral Particle Beam (NPB) weapons systems are planned to perform the ballistic missile defense functions of nuclear weapon/decoy discrimination and warhead kill at appropriate energy levels and ion currents. Negatively charged ions are produced in a specialized ion source and focused into a high quality particle beam. NPB linear accelerators accelerate and steer the negatively charged ions using electric and magnetic fields. After acceleration and steering the neutralizer system strips away extra electrons from ions to form the electrically neutral particle beam. The neutral beam then travels through space to the target unaffected by the Earth's magnetic fields. Continuing technological advances have greatly reduced the size and weight of NPB accelerator systems. Ion current production has been enhanced by over 100 percent with the intermittent addition of cesium at the NPB ion source device. This increase in current is essential to attain the most light weight, compact NPB platforms and minimize expensive launch costs. Addition of cesium into the ion source has been identified by the NPB community as the highest priority risk reduction space experiment necessary prior to planned NPB accelerator experiments and later weapons systems. The NPB Cesium Space Experiment is planned to successfully demonstrate controlled cesium introduction and vaporization into a simulated ion source chamber. Microgravity effects on the cesium deposition will be studied as will the effects of small amounts of cesium on high voltage accelerator components that might be susceptible to electrical insulator break downs. The experiment design will simulate as closely as possible the environment, physical and operational characteristics of the actual NPB ion source.
Low thrust divergent flow cesium-on-tungsten contact ionization electrostatic thrustor for satellite attitude control and stationkeeping missions