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arXiv · 2409.12277

Single Langmuir Probe Diagnostics Device

Angel González-Lizardo·Jairo Rondón·Felix A. Cuadrado-Rodríguez
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Abstract

Seeking to improve and innovate the technology currently used in their research work, the Polytechnic University of Puerto Rico Plasma Laboratory designed and built a portable device able to generate a voltage sweep for an electrostatic probe (namely, a Single Langmuir Probe, or SLP) and to perform the computations necessary to determine the plasma temperature, and density as well as other parameters. The device uses a Raspberry Pi 4 to generate the voltage signal which is amplified through electronic circuitry in the range of -300V to +300V and applied to a SLP. The device is able to capture the current returning from the SLP to extract the relevant information from the IV characteristic and perform the computations necessary to obtain plasma electron density, plasma potential, floating potential, and electron temperature. All data is displayed through a touchscreen by a Graphical user interface developed in PyQT5. This device provides continuous measurement of plasma parameters during the realization of experiments at the laboratory.

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Angel González-Lizardo, Jairo Rondón, Felix A. Cuadrado-Rodríguez. 2024-09-18. Single Langmuir Probe Diagnostics Device. https://arxiv.org/abs/2409.12277

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