Collisionless Magnetorotational Turbulence in Pair Plasmas: Steady-state Dynamics, Particle Acceleration, and Radiative Cooling

Fabio Bacchini; Vladimir Zhdankin; Evgeny A. Gorbunov; Gregory R. Werner; Lev Arzamasskiy; Mitchell C. Begelman; Dmitri A. Uzdensky

arXiv · 2401.01399

Collisionless Magnetorotational Turbulence in Pair Plasmas: Steady-state Dynamics, Particle Acceleration, and Radiative Cooling

Fabio Bacchini·Vladimir Zhdankin·Evgeny A. Gorbunov·Gregory R. Werner·Lev Arzamasskiy·Mitchell C. Begelman·Dmitri A. Uzdensky

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Abstract

We present 3D fully kinetic shearing-box simulations of pair-plasma magnetorotational turbulence with unprecedented macro-to-microscopic scale separation. While retrieving the expected fluid behavior of the plasma at large scales, we observe a steepening of turbulent spectra at kinetic scales and substantial angular-momentum transport linked with kinetic processes. For the first time, we provide a definitive demonstration of nonthermal particle acceleration in kinetic magnetorotational turbulence agnostically of initial conditions, by means of a novel strategy exploiting synchrotron cooling.

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Fabio Bacchini, Vladimir Zhdankin, Evgeny A. Gorbunov, Gregory R. Werner, Lev Arzamasskiy, Mitchell C. Begelman, Dmitri A. Uzdensky. 2024-01-02. Collisionless Magnetorotational Turbulence in Pair Plasmas: Steady-state Dynamics, Particle Acceleration, and Radiative Cooling. https://arxiv.org/abs/2401.01399

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