One-winged butterflies: mode selection for azimuthal magnetorotational instability by thermal convection

Autor:	Mishra, A., Mamatsashvili, G., Seilmayer, M., Stefani, F.
Rok vydání:	2024
Předmět:	Astrophysics - Solar and Stellar Astrophysics Physics - Fluid Dynamics Physics - Plasma Physics
Druh dokumentu:	Working Paper
Popis:	The effects of thermal convection on turbulence in accretion discs, and particularly its interplay with the magnetorotational instability (MRI), are of significant astrophysical interest. Despite extensive theoretical and numerical studies, such an interplay has not been explored experimentally. We conduct linear analysis of the azimuthal version of MRI (AMRI) in the presence of thermal convection and compare the results with our experimental data published before. We show that the critical Hartmann number ($Ha$) for the onset of AMRI is reduced by convection. Importantly, convection breaks symmetry between $m = \pm 1$ instability modes ($m$ is the azimuthal wavenumber). This preference for one mode over the other makes the AMRI-wave appear as a ``one-winged butterfly''. Comment: 11 pages, 5 figures, accepted for publication in the Journal of Fluid Mechanics
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2403.09764 Zobrazit plný text záznamu View this record from Arxiv