This letter proposes a new tomographic reconstruction procedure based on the Laplacian eigenfunction (LEF) patterns, which are independent of the plasma cross-section and do not require the flux surface information. The process is benchmarked for the experimental data of Heliotron J plasma and the results are compared with the least-squares approximation by a Phillips–Tikhonov (PT)-type regularization, which is widely used as the standard technique for tomographic reconstruction. The reconstruction based on the LEF is found to be capable of determining the magnetic axis at different time locations efficiently in comparison with the PT-type regularization.

中文翻译：

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基于拉普拉斯特征函数的层析成像重建新技术

这封信提出了一种基于拉普拉斯特征函数（LEF）模式的新层析重建程序，该模式与等离子体横截面无关，不需要通量表面信息。该过程以Heliotron J等离子体的实验数据为基准，并通过Phillips–Tikhonov（PT）型正则化将结果与最小二乘近似法进行比较，该方法被广泛用作层析重建的标准技术。与PT型正则化相比，发现基于LEF的重构能够有效地确定不同时间位置的磁轴。