中国“人造太阳”EAST实验证实托卡马克密度自由区的存在

Core Insights - The research team at the EAST facility in Hefei, China, has confirmed the existence of a "density-free zone" in tokamak operations, based on the theory of boundary plasma-wall interaction self-organization [1][5]. Group 1: Research Findings - The study developed a theoretical model (PWSO) that highlights the critical role of boundary radiation in triggering the density limit and reveals the physical mechanisms behind it [5]. - The experiments utilized a fully metallic wall environment and methods such as electron cyclotron resonance heating to reduce boundary impurity sputtering, which delayed the onset of the density limit and plasma disruption [5]. - The results of the experiments aligned closely with the predictions of the PWSO theory, marking the first confirmation of the tokamak density-free zone [5]. Group 2: Implications for Fusion Power - Higher density operation is essential for improving the economic viability of fusion energy, as fusion power is proportional to the square of fuel density [3]. - The understanding of the density limit and the newly identified density-free zone provides significant physical basis for high-density operation in tokamaks, which is crucial for future fusion reactors [5].