Current-driven instabilities in weakly ionized disks

TL;DR

This paper investigates the Hall instability in weakly ionized, rotating astrophysical disks, focusing on axisymmetric perturbations in incompressible fluids with magnetic fields, which are crucial for understanding star and planet formation.

Contribution

It introduces a detailed analysis of Hall instability in weakly ionized disks, extending previous MHD studies to include axisymmetric perturbations in incompressible fluids with complex magnetic fields.

Findings

Hall instability can occur in weakly ionized disks under certain magnetic field configurations.

The instability influences angular momentum transfer and density stratification.

Results provide insights into star and planet formation processes.

Abstract

Cool weakly ionized gaseous rotating disk form the basis for many models in astrophysics objects. Instabilities against perturbations in such disks play an important role in the theory of the formation of stars and planets. Traditionally, axisymmetric magnetohydrodynamic (MHD) and recently Hall-MHD instabilities have been thoroughly studied as providers of an efficient mechanism for radial transfer of angular momentum, and of density radial stratification. In the current work, the Hall instability against axisymmetric perturbations in incompressible rotating fluid in external poloidal and toroidal magnetic field is considered.