The aim of the present study is to perform a theoretical analysis of different strategies to stabilize energetic-ion-driven resistive interchange mode (EIC) in LHD plasma. We use a reduced MHD for the thermal plasma coupled with a gyrofluid model for the energetic particles (EP) species. The hellically trapped EP component is introduced through a modification of the drift frequency to include their precessional drift. The stabilization trends of the 1/1 EIC observed experimentally with respect to the thermal plasma density and temperature are reproduced by the simulations, showing a reasonable agreement with the data. The LHD operation scenarios with stable 1/1 EIC are identified, leading to the stabilization of the 1/1 EIC if the thermal plasma density and temperature are above a given threshold. The 1/1 EIC are also stabilized if the rotational transform is modified in a way that the 1/1 rational surface is located further away than 0.9 times the normalized radius, or the magnetic shear in the plasma periphery is enhanced. Also, LHD discharges with large magnetic fields show a higher EIC destabilization threshold with respect to the thermal plasma density. If the perpendicular NBI deposition region is moved further inward than 0.875 times the normalized radius the 1/1 EIC are also stabilized. In addition, increasing the perpendicular NBI voltage such that the EP energy is higher than 30 keV stabilizes the 1/1 EIC. Moreover, Deuterium plasmas show a higher stability threshold for the 1/1 EIC than Hydrogen plasmas. The experimental data shows a larger time interval between EIC events as the power of the tangential NBI is increased providing that the perpendicular NBI power is at least 13 MW. This implies a stabilizing effect of the tangential NBI.
Gyrokinetic Theory of Linear Gravitational Flute Interchanges with Flow Shear Stabilization
University of Maryland, College Park（马里兰大学帕克分校）；Institute for Research in Electronics & Applied Physics, University of Maryland, College Park（马里兰大学电子与应用物理研究所）；Gridfire Inc（Gridfire公司）
Effect of externally applied resonant magnetic perturbations on resistive tearing modes
State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology（华中科技大学电磁工程与技术国家重点实验室）；Max-Planck-Institut für Plasmaphysik, EURATOM association（德国马普等离子体物理研究所，欧洲原子能共同体联合机构）
Real frequency tearing layers with parallel dynamics and the effect on locking and resistive wall modes
在等离子体坐标系中具有实频率的撕裂模式（即，除了由于$E\times B$旋转引起的多普勒频移之外）具有潜在的重要性，因为它们对锁定过程有影响。特别是，它最近被证明[J。Finn，A. J. Cole和D. P. Brennan，Phys. Plasmas（Letters），22：120701，2015]，在存在所施加的误差场的情况下等离子体上的麦克斯韦扭矩对于具有接近边缘稳定性的实频率的撕裂模式被显著修改。此外，它是已知的[J。Finn和R. A. Gerwin，Phys. Plasmas，3：2344，1996]，如果撕裂模式具有接近边缘稳定性的实频率，则电阻壁撕裂模式可以通过旋转而在其无壁极限以下不稳定。在本文中，我们首先推导出撕裂模色散关系与压力梯度，磁力线曲率和平行动力学的连续惯性（RI）制度，忽略的$E\times B$漂移和垂直电阻率的发散。结果表明，在忽略垂直电阻率和$E\times B$漂移发散的简化模型中，出现了通常的Glasser效应，即包含实频率的环形效应。我们还发现，使用一个类似的简单的模型，令人惊讶的结果，在粘阻制度的压力梯度，有利的曲率由于环形效应，和平行的动力学，一个类似的Glasser-like效应被发现，我们表明，在这两个制度的撕裂模式的存在与复杂的频率附近的静电电阻交换模式与复杂的频率。我们讨论了锁定到一个错误字段的效果和显着降低的门槛不稳定的…
Experimental Evidence for Increased Particle Fluxes Due to a Change in Transport at the Separatrix near Density Limits on Alcator C-Mod
MIT Plasma Science and Fusion Center（麻省理工学院等离子体科学与聚变中心）；Commonwealth Fusion Systems（联邦聚变系统）；University of California, San Diego（加利福尼亚大学圣迭戈分校）；Institute of Physics, University of Greifswald（格赖夫斯瓦尔德大学物理研究所）
