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arXiv · 1810.12428

Inertial Kinetic-Alfv\'en Turbulence

Vadim Roytershteyn·Stanislav Boldyrev·Gian Luca Delzanno·Christopher H. K. Chen·Daniel Grošelj·Nuno F. Loureiro
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Abstract

Recent observational and analytical studies suggested that a new regime of kinetic turbulence may exist in plasma environments with low electron beta (Chen and Boldyrev, 2017). Such a regime, termed inertial kinetic-Alfv\'en turbulence, is relevant for the solar corona, Earth's magnetosheath, and other astrophysical systems where the electron and ion plasma beta parameters satisfy the condition $\beta_e\ll \beta_i\lesssim 1$. In this paper we present kinetic numerical simulations that confirm existence of the iKAW regime. Specifically, the simulations demonstrate a transition at scales below electron inertial length $d_e$ when $\beta_e\ll \beta_i\lesssim 1$. Spectral slopes and other statistical properties of turbulence at sub-$d_e$ scales are consistent with the phenomenological theory of inertial kinetic-Alfv\'en turbulence proposed by Chen and Boldyrev (2017) and with the recent observations in the Earth's magnetosheath.

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Vadim Roytershteyn, Stanislav Boldyrev, Gian Luca Delzanno, Christopher H. K. Chen, Daniel Grošelj, Nuno F. Loureiro. 2018-10-29. Inertial Kinetic-Alfv\'en Turbulence. https://arxiv.org/abs/1810.12428

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