Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding
orcid:0000-0002-1171-8603 In the Large Helical Device, the divertor detachment has been attempted by application of resonant magnetic perturbation (RMP) field and Ne gas puffing in electron cyclotron resonance- heated discharges for compatibility of high central electron temperature and low divertor...
Published in: | Plasma and Fusion Research |
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Language: | English |
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The Japan Society of Plasma Science and Nuclear Fusion Research
2022
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Online Access: | https://nifs-repository.repo.nii.ac.jp/record/11155/files/pfr2022_17-2402022.pdf |
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ftninstfusionsci:oai:nifs-repository.repo.nii.ac.jp:00011155 2023-10-29T02:36:01+01:00 Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding OISHI, Tetsutarou OISHI, Tetsutaro KOBAYASHI, Masahiro TAKAHASHI, Hiromi HAYASHI, Yuki MUKAI, Kiyofumi MORITA, Shigeru GOTO, Motoshi KAWAMOTO, Yasuko KAWATE, Tomoko MASUZAKI, Suguru SUZUKI, Chihiro KAWAMURA, Gakushi MOTOJIMA, Gen SEKI, Ryosuke 2022-04-22 application/pdf https://nifs-repository.repo.nii.ac.jp/record/11155/files/pfr2022_17-2402022.pdf eng eng The Japan Society of Plasma Science and Nuclear Fusion Research 10.1585/pfr.17.2402022 Publisher version https://doi.org/10.1585/pfr.17.2402022 Plasma and Fusion Research Special Issue 1 17 2402022 AA12346675 1880-6821 https://nifs-repository.repo.nii.ac.jp/record/11155/files/pfr2022_17-2402022.pdf (c) 2022 The Japan Society of Plasma Science and Nuclear Fusion Research plasma spectroscopy extreme ultraviolet vacuum ultraviolet magnetically confined fusion impurity seeding resonant magnetic perturbation divertor detachment VoR 2022 ftninstfusionsci https://doi.org/10.1585/pfr.17.2402022 2023-09-30T20:24:18Z orcid:0000-0002-1171-8603 In the Large Helical Device, the divertor detachment has been attempted by application of resonant magnetic perturbation (RMP) field and Ne gas puffing in electron cyclotron resonance- heated discharges for compatibility of high central electron temperature and low divertor heat load. Two kinds of divertor detachment phases were observed. The first one appeared transiently just after the Ne gas puffing (1st detachment), and the second one appeared steadily in the latter half of the discharge (2nd detachment). Space-resolved extreme ultraviolet spectroscopy revealed that NeVI-NeVIII emissions increased slightly outside the last closed flux surface (LCFS), while NeIX and NeX emissions increased inside the LCFS in the 1st detachment phase. Although in the 1st detachment the divertor heat load was significantly reduced, the central electron temperature also decreased because the Ne ions were penetrated inside the LCFS as a radiation source. In the 2nd detachment phase, NeVI-NeVIII emissions increased outside the LCFS while NeIX and NeX emissions kept low intensity inside the LCFS. In this phase, low divertor heat load and high central electron temperature were obtained simultaneously because the Ne ions were localized outside the LCFS as a radiation source. The profile measurements of Ne emission show that the edge island structure created by the RMP application impacts on the impurity emission distribution, where the peak of the emission shifts radially stepwise as the detachment proceeds. journal article Other/Unknown Material Edge Island National Institute for Fusion Science: NIFS Repository Plasma and Fusion Research 17 0 2402022 2402022 |
institution |
Open Polar |
collection |
National Institute for Fusion Science: NIFS Repository |
op_collection_id |
ftninstfusionsci |
language |
English |
topic |
plasma spectroscopy extreme ultraviolet vacuum ultraviolet magnetically confined fusion impurity seeding resonant magnetic perturbation divertor detachment |
spellingShingle |
plasma spectroscopy extreme ultraviolet vacuum ultraviolet magnetically confined fusion impurity seeding resonant magnetic perturbation divertor detachment OISHI, Tetsutarou OISHI, Tetsutaro KOBAYASHI, Masahiro TAKAHASHI, Hiromi HAYASHI, Yuki MUKAI, Kiyofumi MORITA, Shigeru GOTO, Motoshi KAWAMOTO, Yasuko KAWATE, Tomoko MASUZAKI, Suguru SUZUKI, Chihiro KAWAMURA, Gakushi MOTOJIMA, Gen SEKI, Ryosuke Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
topic_facet |
plasma spectroscopy extreme ultraviolet vacuum ultraviolet magnetically confined fusion impurity seeding resonant magnetic perturbation divertor detachment |
description |
orcid:0000-0002-1171-8603 In the Large Helical Device, the divertor detachment has been attempted by application of resonant magnetic perturbation (RMP) field and Ne gas puffing in electron cyclotron resonance- heated discharges for compatibility of high central electron temperature and low divertor heat load. Two kinds of divertor detachment phases were observed. The first one appeared transiently just after the Ne gas puffing (1st detachment), and the second one appeared steadily in the latter half of the discharge (2nd detachment). Space-resolved extreme ultraviolet spectroscopy revealed that NeVI-NeVIII emissions increased slightly outside the last closed flux surface (LCFS), while NeIX and NeX emissions increased inside the LCFS in the 1st detachment phase. Although in the 1st detachment the divertor heat load was significantly reduced, the central electron temperature also decreased because the Ne ions were penetrated inside the LCFS as a radiation source. In the 2nd detachment phase, NeVI-NeVIII emissions increased outside the LCFS while NeIX and NeX emissions kept low intensity inside the LCFS. In this phase, low divertor heat load and high central electron temperature were obtained simultaneously because the Ne ions were localized outside the LCFS as a radiation source. The profile measurements of Ne emission show that the edge island structure created by the RMP application impacts on the impurity emission distribution, where the peak of the emission shifts radially stepwise as the detachment proceeds. journal article |
format |
Other/Unknown Material |
author |
OISHI, Tetsutarou OISHI, Tetsutaro KOBAYASHI, Masahiro TAKAHASHI, Hiromi HAYASHI, Yuki MUKAI, Kiyofumi MORITA, Shigeru GOTO, Motoshi KAWAMOTO, Yasuko KAWATE, Tomoko MASUZAKI, Suguru SUZUKI, Chihiro KAWAMURA, Gakushi MOTOJIMA, Gen SEKI, Ryosuke |
author_facet |
OISHI, Tetsutarou OISHI, Tetsutaro KOBAYASHI, Masahiro TAKAHASHI, Hiromi HAYASHI, Yuki MUKAI, Kiyofumi MORITA, Shigeru GOTO, Motoshi KAWAMOTO, Yasuko KAWATE, Tomoko MASUZAKI, Suguru SUZUKI, Chihiro KAWAMURA, Gakushi MOTOJIMA, Gen SEKI, Ryosuke |
author_sort |
OISHI, Tetsutarou |
title |
Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
title_short |
Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
title_full |
Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
title_fullStr |
Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
title_full_unstemmed |
Spatial Profiles of NeVI-NeX Emission in ECR-Heated Discharges of the Large Helical Device with Divertor Detachment Induced by RMP Application and Ne Impurity Seeding |
title_sort |
spatial profiles of nevi-nex emission in ecr-heated discharges of the large helical device with divertor detachment induced by rmp application and ne impurity seeding |
publisher |
The Japan Society of Plasma Science and Nuclear Fusion Research |
publishDate |
2022 |
url |
https://nifs-repository.repo.nii.ac.jp/record/11155/files/pfr2022_17-2402022.pdf |
genre |
Edge Island |
genre_facet |
Edge Island |
op_relation |
10.1585/pfr.17.2402022 Publisher version https://doi.org/10.1585/pfr.17.2402022 Plasma and Fusion Research Special Issue 1 17 2402022 AA12346675 1880-6821 https://nifs-repository.repo.nii.ac.jp/record/11155/files/pfr2022_17-2402022.pdf |
op_rights |
(c) 2022 The Japan Society of Plasma Science and Nuclear Fusion Research |
op_doi |
https://doi.org/10.1585/pfr.17.2402022 |
container_title |
Plasma and Fusion Research |
container_volume |
17 |
container_issue |
0 |
container_start_page |
2402022 |
op_container_end_page |
2402022 |
_version_ |
1781059593640607744 |