The resonant magnetic perturbation (RMP) island introduced in the stochastic edge of the large helical device (LHD) plasma plays an important role in the stabilization of the plasma detachment (Kobayashi et al 2013 Nucl. Fusion53 093032). The plasma enters in the sustained detachment phase in the presence of an RMP once the line averaged density exceeds a critical value with a given input power. During detachment the enhanced radiation from the stochastic edge of the LHD undergoes several spatiotemporal changes which are studied quantitatively by an infrared imaging video bolometer (IRVB) diagnostic. The experimental results are compared qualitatively and quantitatively with the radiation predicted by the 3D transport simulation with fluid model, EMC3-EIRENE. A fair amount of qualitative agreement, before and after the detachment, is reported. The issue of overestimated radiation from the model is addressed by changing the free parameters in the EMC3-EIRENE code till the total radiation and the radiation profiles match closely, within a factor of two with the experimental observations. A better quantitative match between the model and the experiment is achieved at higher cross-field impurity diffusion coefficient and lower sputtering coefficient after the detachment. In this article a comparison, the first of its kind, is established between the quantified radiation from the experiments and the synthetic image obtained from the simulation code. This exercise is aimed towards validating the model assumptions against the experimentally measured radiation.
大型螺旋装置（LHD）等离子体随机边缘中引入的共振磁扰动（RMP）岛在等离子体脱靶的稳定中起着重要作用（Kobayashi et al 2013 Nucl. Fusion 53 09353）。在给定输入功率下，一旦线平均密度超过临界值，等离子体便在存在RMP的情况下进入持续脱靶阶段。在脱靶期间，LHD随机边缘增强的辐射经历了若干时空变化，这些变化通过红外视频测辐射热计（IRVB）诊断进行了定量研究。实验结果与使用流体模型EMC3-EIRENE的三维输运模拟所预测的辐射进行了定性和定量比较。在脱靶前后，报告了相当程度的定性一致性。通过改变EMC3-EIRENE代码中的自由参数，使总辐射和辐射分布与实验观测在两倍因子内紧密匹配，从而解决了模型辐射高估的问题。在脱靶后，通过更高的杂质横向扩散系数和更低的溅射系数，模型与实验之间实现了更好的定量匹配。本文首次将实验测量的辐射与模拟代码获得的合成图像进行了定量对比。该工作旨在验证模型假设与实验测量辐射的一致性。