A generalized effective potential for differentially rotating plasmas

Ebrahimi, Fatima [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000331095367); Haywood, Alexander [Princeton Univ., NJ (United States)] (ORCID:0000000333134032)

doi:10.1063/5.0251633

DOE OSTI · 2530997

A generalized effective potential for differentially rotating plasmas

Ebrahimi, Fatima [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000331095367)·Haywood, Alexander [Princeton Univ., NJ (United States)] (ORCID:0000000333134032)

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Abstract

Global stability of differentially rotating plasma is investigated using a generalized effective potential. We first, for a current-free system, obtain a general form of an effective potential in terms of the free energies of global curvature and gradients of rotation for non-axisymmetric disturbances. We then examine the stability of differentially rotating disks for several rotation profiles and present the associated effective potential for the onset of these instabilities in the MHD regime. In particular, results for global axisymmetric magnetorotational instability as well as local and global non-axisymmetric modes are presented. The latter constitute two distinct non-axisymmetric modes, a high frequency local MRI and a global low-frequency non-axisymmetric mode (the magneto-curvature mode, introduced in Ebrahimi and Pharr [Astrophys. J. 936, 145 (2022)]), confined either between two Alfvénic resonances or an Alfvénic resonance and a boundary.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY Doppler effect Fluid flows Fundamental physics Plasma instabilities Plasma waves Rayleigh's criterion

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Ebrahimi, Fatima [Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000331095367), Haywood, Alexander [Princeton Univ., NJ (United States)] (ORCID:0000000333134032). 2025-03-14. A generalized effective potential for differentially rotating plasmas. https://doi.org/10.1063/5.0251633

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