A theoretical model is presented that for the first time matches experimental measurements of the pedestal width-height Diallo scaling in the low-aspect-ratio high-β tokamak NSTX. Combining linear gyrokinetics with self-consistent pedestal equilibrium variation, kinetic-ballooning, rather than ideal-ballooning plasma instability, is shown to limit achievable confinement in spherical tokamak pedestals. Simulations are used to find the novel Gyrokinetic Critical Pedestal constraint, which determines the steepest pressure profile a pedestal can sustain subject to gyrokinetic instability. Gyrokinetic width-height scaling expressions for NSTX pedestals with varying density and temperature profiles are obtained. These scalings for STs depart significantly from that of conventional aspect ratio tokamaks.

中文翻译：

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球形托卡马克等离子体中的动力学气球限制基座

提出了一个理论模型，该模型首次与低纵横比高的基座宽度-高度 Diallo 缩放的实验测量相匹配。β托卡马克 NSTX。将线性回旋动力学与自洽基座平衡变化相结合，动力学气球，而不是理想气球等离子体不稳定性，被证明可以限制球形托卡马克基座中可实现的限制。模拟用于找到新颖的回旋临界基座约束，该约束确定基座在回旋不稳定的情况下可以承受的最陡压力分布。获得了具有不同密度和温度分布的 NSTX 基座的回旋宽度-高度缩放表达式。 ST 的这些缩放比例与传统纵横比托卡马克的缩放比例显着不同。