Study of Potential Structural Reformation with multi-channel measurements using heavy ion beam

使用重离子束进行多通道测量的潜在结构改造研究

• 批准号: 12480129
• 负责人: FUJISAWA Akihide
• 金额: $ 8.26万
• 依托单位: National Institute for Fusion Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12480129/
• 关键词: CHS; HIBP; transport Barrier; Self-excited Oscillation; Helical Plasma; Radial Elecrtric Field; Bifurcation; Plasma Fluctuation; プラズマ振動; 電位計測; 分岐・遷移現象; 自励振動; 構造形成

In the first two fiscal years from 2000 to 2001, we had constructed a new heavy ion beam probe (HIBP) system on CHS in addition to the old HIBP system. The new HIBP is located at the position away from the old one by 90 degree in toroidal direction. During this period of the construction, we had also made experimental efforts to obtain further understanding of bifurcation characteristics. In these experiments, we have obtained new findings about patterns of bifurcation and existence of hysteresis for realization of the status with improved confinement. These results have been published in Nuclear Fusion. Furthermore, the integrated paper including the results obtained in the phase when CHS is in the Higashiyama site has been also published in the book entitled 'Bifurcation phenomena in plasmas'. In the fiscal year 2001, the construction of the new HIBP has been finished, and the first experiments using two HIBP systems have been done on the ECR-heated CHS plasma with a low electron density of 0.5x10^<13> cm^<-3>. The simultaneous measurements at two different radial positions with these two HIBPs give us information of spatio-temporal evolution of potential structure during electric pulsation (self-organized oscillation). The result has been presented as a post dead line paper in 19^<th> IAEA conference on fusion energy. The outline of the results is following, i) During the pulsation, the potential drop propagates from the center to the outside, and the propagation is quite high. If we express the propagation as diffusion process, the coefficient is D-100m^2/s. ii) It is found that the edge density is strongly correlated with central potential behavior. The observation shows non-local nature of this phenomenon, iii) In the same series of discharges, coherent fluctuation has been observed in potential. The fluctuation is considered to relate with Alfven modes and the corresponding displacement of magnetic surface has been deduced.

在2000年至2001年的前两个财政年度，除了旧的重离子束探针（HIBP）系统外，我们还在CHS上建造了新的重离子束探针（HIBP）系统。新的HIBP位于与旧HIBP成90度环向的位置。在此期间的建设，我们也作出了实验努力，以获得进一步了解的分叉特性。在这些实验中，我们得到了新的发现模式的分叉和存在的滞后实现的状态与改进的限制。这些结果已发表在《核聚变》上。此外，包括CHS在东山站点的阶段中获得的结果的综合论文也已发表在题为“等离子体中的分叉现象”的书中。在2001财政年度，新的HIBP的建设已经完成，并使用两个HIBP系统的第一次实验已经在ECR加热的CHS等离子体与低电子密度的0.5 × 10 ^<13>cm^2<-3>。在两个不同的径向位置与这两个HIBPs的同时测量给我们的电位结构的时空演化过程中的电脉动（自组织振荡）的信息。该结果已在1999年国际原子能<th>机构聚变能会议上发表。结果表明：（1）在脉动过程中，电位降由中心向外传播，且传播速度较快;若将传播过程表示为扩散过程，则传播系数为D-100 m^2/s。ii）发现边缘密度与中心势行为密切相关。观察表明，这种现象的非局部性质，iii）在同一系列的放电，相干波动已被观察到的电位。我们认为这种涨落与阿尔芬模有关，并推导出了相应的磁面位移。

项目成果

A. Fujisawa et al.: "Prescription for density profile reconstruction using a heavy ion beam probe."Submitted to Review of Scientific Instruments.

A. Fujisawa 等人：“使用重离子束探针重建密度剖面的处方。”已提交给科学仪器审查。

藤澤彰英他: "Transport barriers and bifurcation characteristics in stellarators"Plasma Physics of Controlled Fusion. 44. A1-A18 (2001)

Akihide Fujisawa 等人：“仿星器中的传输势垒和分叉特性”受控聚变的等离子体物理学 44. A1-A18 (2001)。

藤澤彰英他: "Prescription for density profile reconstruction using a heavy ion beam probe"Review of Scientific Instruments.

Akihide Fujisawa 等人：“使用重离子束探针重建密度剖面的处方”科学仪器评论。

A. Fujisawa, ed. S.-I Itoh and Y. Kawai: "Bifurcation phenomena associated with radial electric field in a toroidal helical plasma, in Bifurcation Phenomena in Plasmas"Kyushu University. (2002)

A.藤泽编辑。

A.Fujisawa et al.: "Experimental study of the bifurcation nature of the electrostatic potential of a toroidal helical plasma"Physics of Plasmas. 7・10. 4152-4183 (2000)

A.Fujisawa等：“环形螺旋等离子体静电势分叉性质的实验研究”等离子体物理学7・10（2000）。