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arXiv · 1901.08308

Determining the Dominant Acceleration Mechanism during Relativistic Magnetic Reconnection in Large-scale Systems

Fan Guo·Xiaocan Li·William Daughton·Patrick Kilian·Hui Li·Yi-Hsin Liu·Wangcheng Yan·Dylan Ma
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Abstract

While a growing body of research indicates that relativistic magnetic reconnection is a prodigious source of particle acceleration in high-energy astrophysical systems, the dominant acceleration mechanism remains controversial. Using a combination of fully kinetic simulations and theoretical analysis, we demonstrate that Fermi-type acceleration within the large-scale motional electric fields dominates over direct acceleration from non-ideal electric fields within small-scale diffusion regions. This result has profound implications for modeling particle acceleration in large-scale astrophysical problems, since it opens up the possiblity of modeling the energetic spectra without resolving microscopic diffusion regions.

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Fan Guo, Xiaocan Li, William Daughton, Patrick Kilian, Hui Li, Yi-Hsin Liu, Wangcheng Yan, Dylan Ma. 2019-01-24. Determining the Dominant Acceleration Mechanism during Relativistic Magnetic Reconnection in Large-scale Systems. https://doi.org/10.3847/2041-8213/ab2a15

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