A runaway avalanche can result in a conversion of the initial plasma current into a relativistic electron beam in high-current tokamak disruptions. We investigate the effect of massive material injection of deuterium–noble gas mixtures on the coupled dynamics of runaway generation, resistive diffusion of the electric field and temperature evolution during disruptions in the deuterium–tritium phase of ITER operations. We explore the dynamics over a wide range of injected concentrations and find substantial runaway currents, unless the current quench time is intolerably long. The reason is that the cooling associated with the injected material leads to high induced electric fields that, in combination with a significant recombination of hydrogen isotopes, leads to a large avalanche generation. Balancing Ohmic heating and radiation losses provides qualitative insights into the dynamics; however, an accurate modelling of the temperature evolution based on energy balance appears crucial for quantitative predictions.

中文翻译：

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在存在大量材料注入的情况下，ITER 操作的 DT 阶段的失控动力学

在大电流托卡马克中断中，失控雪崩可导致初始等离子体电流转换为相对论电子束。我们研究了在 ITER 操作的氘-氚相中断期间，大量材料注入氘-稀有气体混合物对失控产生、电场的电阻扩散和温度演变的耦合动力学的影响。我们探索了大范围注入浓度的动力学并发现了大量的失控电流，除非电流失超时间长得令人无法忍受。原因是与注入材料相关的冷却会导致高感应电场，再加上氢同位素的显着重组，会导致大量雪崩的产生。平衡欧姆加热和辐射损失提供了对动力学的定性见解；然而，基于能量平衡的温度演变的准确建模对于定量预测似乎至关重要。