Plasma and Fusion Research

Volume 14, 2401156 (2019)

Regular Articles


Characteristics of Upstream and Downstream Plasma Parameters from Langmuir Probes and Visible Spectrometers in the D-Module of GAMMA 10/PDX
Takaaki IIJIMA, Toshiki HARA, Kunpei NOJIRI, Akihiro TERAKADO, Md. Shahinul ISLAM, Tsubasa YOSHIMOTO, Sotaro YAMASHITA, Naomichi EZUMI, Mizuki SAKAMOTO and Yousuke NAKASHIMA
Plasma Research Center, University of Tsukuba, Tsukuba 305-8577, Japan
(Received 30 September 2018 / Accepted 3 June 2019 / Published 25 September 2019)

Abstract

Plasma parameters in the upstream and downstream regions in the divertor simulation experimental module (D-module) of the tandem mirror plasma device GAMMA 10/PDX were conducted using Langmuir probes. The detached plasma was produced using hydrogen puffing. In the upstream region, the electron temperature decreased from 30 to 7 eV, and the electron density increased. On the other hand, rollover of ne at the V-shaped corner was observed in the downstream region. Increasing Hα/Hβ at the corner of the V-shaped target was attributed to the molecular activated recombination processes. Hα/Hβ in the downstream region was different from that in the upstream region. Therefore, the ionization front appeared in the upstream region of the D-module.


Keywords

divertor, detached plasma, molecular activated recombination, GAMMA 10/PDX

DOI: 10.1585/pfr.14.2401156


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