Approaching Detachment in I-mode - Response of Core Confinement and the Edge Pedestal in the ASDEX Upgrade Tokamak
Experiments on nitrogen assisted divertor detachment in the improved energy confinement mode (I-mode) are reported from the ASDEX Upgrade tokamak. When nitrogen is introduced into the divertor and radiation losses cool the divertor plasma down, a loss of core confinement is observed, concomitant wit...
| Autores: | , , , , , , , , , , |
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| Tipo de documento: | artigo |
| Estado: | Versión aceptada para publicación |
| Data de publicação: | 2021 |
| País: | España |
| Recursos: | Universidad de Sevilla (US) |
| Repositório: | idUS. Depósito de Investigación de la Universidad de Sevilla |
| OAI Identifier: | oai:idus.us.es:11441/141183 |
| Acesso em linha: | https://hdl.handle.net/11441/141183 https://doi.org/10.1088/1741-4326/abd7b7 |
| Access Level: | Acceso aberto |
| Palavra-chave: | Confinement Regime Detachment ELM-free I-mode Nitrogen seeding Tokamak |
| Resumo: | Experiments on nitrogen assisted divertor detachment in the improved energy confinement mode (I-mode) are reported from the ASDEX Upgrade tokamak. When nitrogen is introduced into the divertor and radiation losses cool the divertor plasma down, a loss of core confinement is observed, concomitant with an increase in low frequency edge fluctuation levels. The loss in confinement can be compensated and the I-mode can be maintained by additional heating power input. Detachment of the inner divertor leg has been observed for the first time in an I-mode discharge. The outer divertor leg remains attached in these experiments. Good energy confinement properties (H 98(y, 2) = 0.9) during the detachment of the inner divertor leg are reported. |
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