Thomas D M, Leonard A W, Lao L L, Osborne T H, Mueller H W, Finkenthal D F
General Atomics, PO Box 85608, San Diego, California 92186-5608, USA.
Phys Rev Lett. 2004 Aug 6;93(6):065003. doi: 10.1103/PhysRevLett.93.065003.
Localized currents driven by pressure gradients play a pivotal role in the magnetohydrodynamic stability of toroidal plasma confinement devices. We have measured the currents generated in the edge of L- (low) and H- (high confinement) mode discharges on the DIII-D tokamak, utilizing the Zeeman effect in an injected lithium beam to obtain high resolution profiles of the poloidal magnetic field. We find current densities in excess of 1 MA/m2 in a 1 to 2 cm region near the peak of the edge pressure gradient. These values are sufficient to challenge edge stability theories based on specific current formation models.
由压力梯度驱动的局部电流在环形等离子体约束装置的磁流体动力学稳定性中起着关键作用。我们利用注入锂束中的塞曼效应，在DIII-D托卡马克上测量了L（低约束）模和H（高约束）模放电边缘产生的电流，以获得极向磁场的高分辨率分布。我们发现在边缘压力梯度峰值附近1至2厘米区域内的电流密度超过1 MA/m²。这些值足以对基于特定电流形成模型的边缘稳定性理论提出挑战。
