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arXiv · 2208.12569

FastQSL: A Fast Computation Method for Quasi-separatrix Layers

Peijin Zhang·Jun Chen·Rui Liu·Chuanbing Wang
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Abstract

Magnetic reconnection preferentially takes place at the intersection of two separatrices or two quasi-separatrix layers, which can be quantified by the squashing factor Q, whose calculation is computationally expensive due to the need to trace as many field lines as possible. We developed a method (FastQSL) optimized for obtaining Q and the twist number in a 3D data cube. FastQSL utilizes the hardware acceleration of the graphic process unit (GPU) and adopts a step-size adaptive scheme for the most computationally intensive part: tracing magnetic field lines. As a result, it achieves a computational efficiency of 4.53 million Q values per second. FastQSL is open source, and user-friendly for data import, export, and visualization.

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Peijin Zhang, Jun Chen, Rui Liu, Chuanbing Wang. 2022-08-26. FastQSL: A Fast Computation Method for Quasi-separatrix Layers. https://doi.org/10.3847/1538-4357%2Fac8d61

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