Stability analysis of differentially rotating disks with global curvature effects

Instability-driven turbulence plays a crucial role in explaining the accretion process and angular momentum transport in astrophysical disks. Here, we examined the drivers of non-linear transport in differentially rotating systems: instabilities. In particular, this work examined the stability of the Magneto-Rotational Instability (MRI) in the weak-field limit as well as the global non-axisymmetric Magneto-Curvature Instability (MCI) in the strong-field limit (Ebrahimi & Pharr ApJ 936, 2022). Unlike MRI, which is typically concentrated in flow shear regions, MCIs are global distinct low-frequency non-axisymmetric modes driven unstable by global differential rotation and spatial curvature. This work presents linear MHD simulations in an unstratified Keplerian cylinder at various Lunquist numbers, aspect ratios, and flow profiles. These results are compared to ideal and non-ideal linear instability perturbation analysis. Using spectral analysis, we present all branches of instability.