Plasma and Fusion Research

Volume 16, 1202081 (2021)

Rapid Communications


Effects of Electron Temperature Fluctuation on Turbulence Measurement by Langmuir Probe in a Magnetized Helicon Plasma
Yuichi KAWACHI, Shigeru INAGAKI1,2), Makoto SASAKI1,3), Yusuke KOSUGA1,2), Takuma YAMADA4), Yoshihiko NAGASHIMA1,2), Chanho MOON2), Naohiro KASUYA1,2) and Akihide FUJISAWA1,2)
Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan
1)
Research Center for Plasma Turbulence, Kyushu University, Kasuga 816-8580, Japan
2)
Research Institution for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
3)
College of Industrial Technology, Nihon University, Narashino 275-8575, Japan
4)
Faculty of Arts and Science, Kyushu University, Fukuoka 819-0395, Japan
(Received 13 April 2021 / Accepted 4 May 2021 / Published 7 June 2021)

Abstract

Effects of electron temperature fluctuation on measurement of other fluctuations by using of Langmuir probe is investigated in PANTA plasma with finite temperature gradient, where significant electron temperature fluctuations are observed. The temperature fluctuation and its effects are evaluated from spatiotemporal structures of ion saturation current and floating potential, derived by conditional sampling/averaging technique. It is found that electron density fluctuation is in phase with ion saturation current fluctuation, but plasma potential fluctuation is anti-phase with the floating potential fluctuation.


Keywords

turbulence, transport, Langmuir probe

DOI: 10.1585/pfr.16.1202081


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