Interpretation and implementation of an ion sensitive probe as a plasma potential diagnostic
An ion sensitive probe (ISP) is developed as a robust diagnostic for measuring plasma potentials (Φ[subscript P]) in magnetized plasmas. The ISP relies on the large difference between the ion and electron gyroradii (ρ[subscript i]/ρ[subscript e] ∼ 60) to reduce the electron collection at a collector...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Institute of Physics
2011
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| Online Access: | http://hdl.handle.net/1721.1/67491 https://orcid.org/0000-0002-9001-5606 https://orcid.org/0000-0002-7841-9261 |
| Summary: | An ion sensitive probe (ISP) is developed as a robust diagnostic for measuring plasma potentials (Φ[subscript P]) in magnetized plasmas. The ISP relies on the large difference between the ion and electron gyroradii (ρ[subscript i]/ρ[subscript e] ∼ 60) to reduce the electron collection at a collector recessed behind a separately biased wall distance ∼ ρ[subscript i]. We develop a new ISP method to measure the plasma potential that is independent of the precise position and shape of the collector. Φ[subscript P] is found as the wall potential when charged current to the probe collector vanishes during the voltage sweep. The plasma potentials obtained from the ISP match Φ[subscript P] measured with an emissive probe over a wide range of plasma conditions in a small magnetized plasma. |
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