2023/07/26 by J. W. Brooks, Erik Tejero, Brooks, John W. +5
Decision Sciences · Engineering · #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Laser-induced spectroscopy and plasma #Plasma Diagnostics and Applications #Plasma Physics (physics.plasm-ph) #Scientific Measurement and Uncertainty Evaluation
paper · pdf · doi:10.48550/arxiv.2307.14263
openalex publication_date 2023/07/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Plasma impedance probes (PIPs) are a type of RF probe that primarily measure electron density. This work introduces two advancements: a streamlined analytical model for interpreting PIP-monopole measurements and techniques for achieving ≥ 1 MHz time-resolved PIP measurements. The model's improvements include introducing sheath thickness as a measurement and providing a more accurate method for measuring electron density and damping. The model is validated by a quasi-static numerical simulation which compares the simulation with measurements, identifies sources of error, and provides probe design criteria for minimizing uncertainty. The improved time resolution is achieved by introducing higher-frequency hardware, updated analysis algorithms, and a more rigorous approach to RF calibration. Finally, the new model and high-speed techniques are applied to two datasets: a 4 kHz plasma density oscillation resolved at 100 kHz with densities ranging between 2 × 1014 to 3 × 1015 m-3 and a 150 kHz oscillation resolved at 4 MHz with densities ranging between 4 × 1014 to 6 × 1014 m-3.