Plasma and Fusion Research

Volume 15, 2402013 (2020)

Regular Articles

Measurement of Dynamic Retention with Fast Ejecting System of Targeted Sample (FESTA)
Qilin YUE, Kazuaki HANADA1), Makoto OYA2), Shogo MATSUO, Shinichiro KOJIMA, Hiroshi IDEI1), Takumi ONCHI1), Kengoh KURODA1), Naoaki YOSHIDA1), Ryuya IKEZOE1), Yukai LIU3), Makoto HASEGAWA1), Shun SHIMABUKURO1), Aki HIGASHIJIMA1), Takahiro NAGATA1) and Shoji KAWASAKI1)
Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan
1)
Research Institute for Applied Mechanics, Kyushu University, Kasuga 816-8580, Japan
2)
Faculty of Engineering Sciences, Kyushu University, Kasuga 816-8580, Japan
3)
Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
(Received 27 November 2019 / Accepted 24 February 2020 / Published 6 April 2020)

Abstract

Fast Ejecting System of Targeted sAmple called FESTA has been developed to carry out the measurement of dynamic hydrogen retention by a test sample. A sample can be exposed and extracted from the targeted plasma at any time using FESTA, however, when exposing the sample, the test chamber wall gets coated by some hydrogen as it is open to the QUEST vacuum vessel. We refer to this as the plasma-induced background. To measure the amount of hydrogen retained by the sample itself, the contribution from the plasma induced background must be subtracted from the measurements. To measure the accurate dynamic retention from plasma-exposed sample, a background subtraction model has been developed and tested. The initial testing shows that the FESTA system and model can estimate the dynamic hydrogen retention by a target test sample.

Keywords

dynamic retention, hydrogen recycling, plasma wall interaction, plasma-induced background, FESTA

DOI: 10.1585/pfr.15.2402013

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