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arXiv · 2509.11122

Dynamical generation of macroscale magnetic fields and fast flows in a four-component astrophysical plasma

Abstract

We explore the possibility of the generation or amplification of macroscale magnetic fields and flows in a four-component astrophysical dusty plasma composed of mobile massless electrons and positrons, inertial positive ions and negatively charged static dust particles. The investigation demonstrates that when microscopic turbulent ambient plasma energy is predominantly kinetic, a straight dynamo (DY) mechanism is feasible. Conversely, a unified reverse-dynamo/dynamo (RDY/DY) mechanism is possible when the microscopic turbulent ambient plasma energy is primarily magnetic. Additionally, the evolution of Alfvén Mach numbers at the macro- and microscale are significantly affected by plasma species densities and invariant helicities. The potential implications of the present study for astrophysical settings are also highlighted.

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Usman Shazad, M. Iqbal. 2025-09-14. Dynamical generation of macroscale magnetic fields and fast flows in a four-component astrophysical plasma. https://doi.org/10.1088/1402-4896%2Fad7a32

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