Observation of tungsten emission spectra up to W46+ ions in the Large Helical Device and contribution to the study of high-Z impurity transport in fusion plasmas

Author:

Oishi TetsutarouORCID,Morita ShigeruORCID,Kato DaijiORCID,Murakami IzumiORCID,Sakaue Hiroyuki A.,Goto MotoshiORCID,Kawamoto YasukoORCID,Kawate TomokoORCID,Nishimura Ryota,Takahashi HiroyukiORCID,Tobita KenjiORCID

Abstract

Abstract Spectroscopic studies of emissions released from tungsten ions combined with a pellet injection technique have been conducted in Large Helical Device for contribution to the tungsten transport study in tungsten divertor fusion devices and for expansion of the experimental database of tungsten line emissions. The spectral intensities of W5+, W24+–W28+, W37+, W38+, W41+–W43+, W45+, and W46+ emission lines were measured simultaneously over a wide wavelength range from x-ray to visible. Time evolutions of the various tungsten line spectra indicate that the tungsten confinement time depends on the electron density of the plasma and is long in high density plasmas, on the order of seconds, and short in low density plasmas, on the order of sub-seconds. When the confinement time was long, the tungsten ions remained in the plasma until the end of the discharge, changing their dominant charge with the change in electron temperature. When the confinement time was short, the tungsten ions rapidly decreased in all charge states and disappeared. Space-resolved EUV and visible spectroscopy measurements have revealed that tungsten ions stayed in the core region of the plasma with changing their dominant charge state depending on the electron temperature in the discharges with the long confinement time. Detailed analysis of soft x-ray emission suggested that the confinement time increases with density and becomes saturated when the central electron density exceeds 2 × 1013 cm−3.

Funder

NIFS Collaboration Research program

Japan Society for the Promotion of Science

Publisher

IOP Publishing

Reference36 articles.

1. Chapter 1: overview and summary;ITER Physics Basis Editors ITER Physics Expert Group Chairs and Co-Chairs, ITER Joint Central Team and Physics Integration Unit;Nucl. Fusion,1999

2. Tungsten: an option for divertor and main chamber plasma facing components in future fusion devices;Neu;Nucl. Fusion,2005

3. Tritium inventory in ITER plasma-facing materials and tritium removal procedures;Roth;Plasma Phys. Control. Fusion,2008

4. Modelling of measured tungsten spectra from ASDEX upgrade and predictions for ITER;ASDEX Upgrade Team;Plasma Phys. Control. Fusion,2008

5. Tungsten transport and accumulation in JT-60U;The JT-60 Team;J. Nucl. Mater.,2011

Cited by 1 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3