Establishment of high accuracy diagnostic method of highly ionised tungsten ion in high temperature plasmas in next generation fusion devices

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K06658
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear fusion studies
• Research Institution: National Institutes for Quantum and Radiological Science and Technology (2016-2018); Japan Atomic Energy Agency (2015)
• Principal Investigator: Nakano Tomohide 国立研究開発法人量子科学技術研究開発機構, 那珂核融合研究所 先進プラズマ研究部, 上席研究員(定常) (50354593)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 原子分子データ / 原子過程 / 二電子性再結合

Outline of Final Research Achievements

The purpose of this study is to evaluate uncertainties of the calculated W62+ ionization and W63+ recombination cross-sections. Because of difficulties in direct measurement of the cross-sections, evaluation of the uncertainties by direct comparison between calculated and measured cross-sections are not available.
We have developed a method, by which dependence of emission intensities on electron impact energy is cancelled out. The method enables direct comparison of the ratio of W62+ to W63+ emission intensity with the ratio of W63+ recombination to W62+ ionization cross-section. The comparison indicates that uncertainty of the calculated cross-sections is small in a low electron impact energy range but large in a high electron impact energy range. This suggests that further improvement of the calculation is required.

Free Research Field

プラズマ分光学

Academic Significance and Societal Importance of the Research Achievements

計算したW62+電離・W63+再結合断面積は改善すべき部分はあるものの，本研究により初めて精度が評価された断面積を整備した．将来の核融合炉プラズマ中のタングステンイオン密度の導出に本データを用いることによって，その測定値に対する精度（真のタングステンイオン密度が存在する範囲）を評価することが可能である．これは測定を質的に向上させることから，以前より切望されていたデータである．さらなる理論計算の改善により，高電子衝突エネルギーでの精度の向上を目指す．