Calculation and Measurement of the Neutron Emission Spectrum due to Thermonuclear and Higher-Order Reactions in Tokamak Plasmas
Calculation and Measurement of the Neutron Emission Spectrum due to Thermonuclear and Higher-Order Reactions in Tokamak Plasmas
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托卡马克等离子体中热核和高阶反应中子发射光谱的计算和测量
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发表时间：
2003
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通讯作者：
L. Ballabio
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作者：
L. Ballabio
本文建立了一系列用于预测和解释热核氘氚（DT）等离子体中子辐射能谱的解析和数值模型。中子发射的主要成分，由于热燃料离子之间的反应，以及少数组件由于快速（超热）离子的存在下，已被建模。特别地，已经分析了所谓的α粒子撞击中子（AKN）发射，并且发现其携带关于等离子体内部的快α粒子的约束的信息。α粒子携带等离子体中产生的聚变功率的五分之一，并提供等离子体自加热。本论文致力于聚变研究的这一中心奋进和它的研究在当今最大的磁约束装置，托卡马克的可能性，开发的模型已被用于解释的实验数据在第一次氘氚实验（DTE 1）在联合欧洲环（JET）在1997年。这些数据是用乌普萨拉大学中子研究系（INF）研制的磁质子反冲（MPR）型中子谱仪采集的。MPR用于测量DT等离子体的中子发射，代表了高达16 MW的创纪录高聚变功率水平和相应的高质量中子发射观测。在DT等离子体中的这些研究与氘等离子体中14 MeV triton燃耗中子（TBN）发射的理论和经验研究相补充，发现预测的中子能谱能够描述观测结果，导致以前未观察到的光谱特征，如中子发射中非常弱的AKN和TBN特征的积极识别。在这个总结中，所开发的模型以及实验结果。最后，讨论了所提出的模型和实验技术的下一步融合实验，如建议的ITER托卡马克的可能应用。
A series of analytic and numerical models have been developed for the prediction and interpretation of the energy spectrum of the neutron emission from thermonuclear deuteriumtritium (DT) plasmas. The main component of the neutron emission, due to reactions between thermal fuel ions, has been modeled as well as minority components due to the presence of fast (supra-thermal) ions. In particular, the so-called alpha-particle knock-on neutron (AKN) emission has been analyzed and found to carry information on the con- finement of fast alpha particles inside the plasma. The alpha particles carry one fifth of the fusion power generated in the plasma and provide the plasma self-heating. This thesis is devoted to this central endeavor of fusion research and the possibilities for its study in today’s largest magnetic confinement devices, the tokamaks.The developed models have been used for the interpretation of experimental data taken during the first deuterium-tritium experiment (DTE1) at the Joint European Torus (JET) in 1997. The data were taken with a neutron spectrometer of the magnetic proton recoil (MPR) type developed at the Department of Neutron Research (INF) of Uppsala University. The MPR was used to measure the neutron emission from DT plasmas representing record high fusion power levels of up to 16 MW and correspondingly high quality in the neutron emission observations. These studies in DT plasmas were complemented with theoretical and empirical studies of the 14-MeV triton burn-up neutron (TBN) emission from deuterium plasmas.The predicted neutron energy spectra were found to be able to describe observations leading to positive identification of previously unobserved spectral features such as the very weak AKN and TBN signature in the neutron emission. In this summary, the developed models are presented as well as the experimental findings. Finally, a discussion is included of the possible application of the presented models and experimental techniques to next-step fusion experiments such as the proposed ITER tokamak.