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arXiv · 2210.16503

Plasma emission induced by ring-distributed energetic electrons in overdense plasmas

Yao Chen·Zilong Zhang·Sulan Ni·Hao Ning·Chuanyang Li·Yaokun Li
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Abstract

According to the standard scenario of plasma emission, escaping radiations are generated by the nonlinear development of the kinetic bump-on-tail instability driven by a single beam of energetic electrons interacting with plasmas. Here we conduct fully-kinetic electromagnetic particle-in-cell simulations to investigate plasma emission induced by the ring-distributed energetic electrons interacting with overdense plasmas. Efficient excitations of the fundamental (F) and harmonic (H) emissions are revealed with radiation mechanism(s) different from the standard scenario: (1) The primary modes accounting for the radiations are generated through the electron cyclotron maser instability (for the upper-hybrid (UH) and Z modes) and the thermal anisotropic instability (for the whistler (W) mode); the F emission is generated by the nonlinear coupling of the Z and W modes and the H emission by the nonlinear coupling of the UH modes. This presents an alternative mechanism of coherent radiation in overdense plasmas.

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Yao Chen, Zilong Zhang, Sulan Ni, Hao Ning, Chuanyang Li, Yaokun Li. 2022-10-29. Plasma emission induced by ring-distributed energetic electrons in overdense plasmas. https://doi.org/10.1063/5.0108780

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