Role of ion acoustic instability in magnetic reconnection

Li, Dion [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000311749490); Liu, Zhuo [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000309617149); Loureiro, Nuno F. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000197556563)

doi:10.1017/s002237782510113x

DOE OSTI · 3684024

Role of ion acoustic instability in magnetic reconnection

Li, Dion [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000311749490)·Liu, Zhuo [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000309617149)·Loureiro, Nuno F. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000197556563)

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Abstract

We report on a first-principles numerical study of magnetic reconnection in plasmas with different initial ion-to-electron temperature ratios. In cases where this ratio is significantly below unity, we observe intense wave activity in the diffusion region, driven by the ion-acoustic instability. Our analysis shows that the dominant macroscopic effect of this instability is to drive substantial ion heating. In contrast to earlier studies reporting significant anomalous resistivity, we find that anomalous contributions due to the ion-acoustic instability are minimal. These results shed light on the dynamical impact of this instability on reconnection processes, offering new insights into the fundamental physics governing collisionless reconnection.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY plasma instabilities plasma simulation space plasma physics

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Li, Dion [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000311749490), Liu, Zhuo [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000309617149), Loureiro, Nuno F. [Massachusetts Institute of Technology, Cambridge, MA (United States)] (ORCID:0000000197556563). 2026-02-27. Role of ion acoustic instability in magnetic reconnection. https://doi.org/10.1017/s002237782510113x

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