Rotational suppression of the Tayler instability in stellar radiation zones

TL;DR

This paper investigates how stellar rotation influences the stability of magnetic fields in stellar radiation zones, revealing conditions under which rotation can suppress or reduce the Tayler instability, affecting stellar magnetic dynamics.

Contribution

It provides new insights into the rotational effects on magnetic stability, showing that suppression depends on the magnetic field configuration and rotation speed.

Findings

Rapid rotation can suppress instability if the magnetic field decreases with radius.

Instability persists if the magnetic field increases rapidly with radius, despite fast rotation.

Marginally stable magnetohydrodynamic waves can exist where instability is suppressed.

Abstract

The study of the magnetic field in stellar radiation zones is an important topic in modern astrophysics because the magnetic field can play an important role in several transport phenomena such as mixing and angular momentum transport. We consider the influence of rotation on stability of a predominantly toroidal magnetic field in the radiation zone. We find that the effect of rotation on the stability depends on the magnetic configuration of the basic state. If the toroidal field increases sufficiently rapidly with the spherical radius, the instability cannot be suppressed entirely even by a very fast rotation although the strength of the instability can be significantly reduced. On the other hand, if the field increases slowly enough with the radius or decreases, the instability has a threshold and can be completely suppressed in rapidly rotating stars. We find that in the regions where the instability is entirely suppressed a particular type of magnetohydrodynamic waves may exist which are marginally stable.