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Showing 1 to 12 of 12 for “"Retarding Potential Analyzer"”.
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Enhancing retarding potential analyzer energy measurements with micro-aligned electrodes
… reactors, and in silicon processing chambers. A Retarding Potential Analyzer (RPA) is a sensor that measures the ion energy distribution of a plasma. The ion energy influences the ablation of surfaces, or plasma etching, as well as the deposition processes. Integrated circuit foundries could …
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A Framework for Validation and Testing of a CubeSat Retarding Potential Analyzer
Traditionally, Retarding Potential Analyzers (RPAs) operate exclusively on large satellites due to the size, power, and mass constraints posed by nano-satellites like CubeSats. These sensors take in-situ measurements of Earth's atmospheric ion current during a range of time-varied ``retarding" …
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Electronics for a Versatile and Robust Retarding Potential Analyzer for Nano-Satellite Platforms
A retarding potential analyzer (RPA) is an instrument that, when mounted on a satellite in low-Earth orbit, makes in-situ measurements of ion density, temperature and speed relative to the satellite frame. The instrument works by changing the voltage on one of a set of grids and measuring a …
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On the stability of complex ions in ionic liquid Ion sources
… A time of flight mass spectrometer and a retarding potential analyzer were developed specifically for this purpose. The ion beam composition and energy distribution were measured at various temperatures and source voltages for each ionic liquid. With some exceptions, the observed trend was …
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Experimental and theoretical characterization of a Hall thruster plume
… were taken with a Faraday probe and a Retarding Potential Analyzer at various background pressures to correlate changes in current density and ion energy distribution with changes in pressure. Results showed that current density increases linearly with background pressure at any given …
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Development and Test of a Permanent Magnet Helicon Thruster
… a test facility equipped with Langmuir probe and Retarding Potential Analyzer diagnostics for helicon thruster research. A helicon thruster using permanent magnets was also designed and tested. The helicon has several advantages, but the main disadvantage is the use of electromagnets to generate …
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Propulsion mechanisms in a helicon plasma thruster
… is investigated with the goal of identifying potential thrust mechanisms. Performance characteristics such as thrust, specific impulse, ion cost and thrust efficiency are discussed and related to plasma parameters. The design and fabrication of a prototype compact helicon thruster is …
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Radio frequency driven direct current electron beam source
… the cold cathode using a differentially pumped retarding potential analyzer. The measured electron beam energy spectra is related to the time varying cathode sheath potential provided by the rf bias using collisionless Child-Langmuir rf sheath model with good agreement. The electron beam source …
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Investigation of a space propulsion concept using inertial electrostatic confinement
… this study, which used argon as a propellant, a retarding potential analyzer (RPA) was used to measure the exhaust of HIIPER, and results showed the presence of electrons and ions, with ion energies equal to the helicon bias voltage and electron energies on the order of the inner IEC grid …
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Characterization of a piezoelectric transformer plasma source
… in the crystal then generates an electric potential within the aperture of the PTPS. With an electrode pattern of a large annular electrode with a small aperture in the center the generated output voltage is larger than the applied voltage. Near the resonant frequency, the voltage step-up …
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Divergent Plume Reduction of a High-Efficiency Multistage Plasma Thruster
… were collected using a nude Faraday probe and retarding potential analyzer. The data show a significant increase in centerline current with the application of the shield, but due to RPA malfunction and thruster failure the actual change in performance could not be concluded.</p> <p>The …
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Enabling Validation of a CubeSat Compatible Wind Sensor
The Ram Energy Distribution Detector (REDD) is a new CubeSat-compatible space science instrument that measures neutral wind characteristics in the upper atmosphere. Neutral gas interactions with plasma in the ionosphere/thermosphere are responsible for spacecraft drag, radio frequency disturbances …