ICIS2023 - 20th International Conference on Ion Sources September 17-22, 2023

Evaluation of H-/D- Density Using Langmuir Probe Measurement in a Cs Seeded Negative Ion Source

Not scheduled

20m

Victoria Conference Centre

Poster (by default) Beam Formation, Extraction, Transport, and Diagnostics Tuesday

Speaker

Engrhyt Rattanawongnara (SOKENDAI university)

Description

Negative-ion density measurement in negative-ion sources is still in demand for improving the design and efficiency of the sources [1,2].
A new analysis method called the 'electron reduction Langmuir probe model' is developed for an area that cannot use a laser-related measurement [3], such as inside the extraction hole.
A validity check of the new analysis is performed in hydrogen and deuterium plasma for utilizing and improving the technique.
Langmuir probe-assisted photodetachment [4,5,6] calibrated with cavity ring down line integral [7] is a standard for negative ion density.
A linear correlation between negative ion density from the electron reduction method and the standard shows that the new analysis method can be a replacement with careful calibration.
[1] M. Bacal, Plasma Sources Sci. Technol. 2, 190 (1993)
[2] K. Tsumori and M. Wada, New J. Phys. 19 045002 (2017).
[3] E. Rattanawongnara et al., Plasma and Fusion Research 18, 1401020 (2023).
[4] M. Bacal, Rev. Sci. Instrum. 71, 3981 (2000).
[5] N. Oudini et al., Plasma Sources Sci. Technol. 28, 065016 (2019).
[6] N. Sirse et al., Plasma Sources Sci. Technol. 20, 055003 (2011).
[7] S. Masaki et al., Rev. Sci. Instrum. 91, 013512 (2020).