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arXiv · 2606.21853

Plasma Flow Generation and Particle Acceleration from Expanding Magnetic Bubbles

Yang Zhang·Brandon K. Russell·Geoffrey Pomraning·Lan Gao·Xiaocan Li·Adam Stainer·William Daughton·Chuanfei Dong·Liang Wang·Peiyun Shi·Kian Orr·Hantao Ji
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Abstract

Impulsive plasma dynamics in the laboratory are often driven by rising electric currents, yet their quantitative plasma response has not been well established. By means of fully kinetic particle-in-cell simulations and laser-driven capacitor-coil experiments, we show that a rising current expels plasma, forming an expanding magnetic bubble and accelerating particles. The expansion front velocity scales with the Alfv\'en speed determined by the magnetic field at its inner edge and the plasma density at its outer edge. This mechanism establishes impulsive current drive as a fundamental way that generates plasma flows and accelerates particles in laboratory plasmas, with potential relevance to astrophysics.

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Yang Zhang, Brandon K. Russell, Geoffrey Pomraning, Lan Gao, Xiaocan Li, Adam Stainer, William Daughton, Chuanfei Dong, Liang Wang, Peiyun Shi, Kian Orr, Hantao Ji. 2026-06-20. Plasma Flow Generation and Particle Acceleration from Expanding Magnetic Bubbles. https://doi.org/10.1103/yw76-d6kh

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