Spin-down by dynamo action in simulated radiative stellar layers

Abstract

The evolution of a star is influenced by its internal rotation dynamics through transport and mixing mechanisms, which are poorly understood. Magnetic fields can play a role in transporting angular momentum and chemical elements, but the origin of magnetism in radiative stellar layers is unclear. Using global numerical simulations, we identify a subcritical transition to turbulence due to the generation of a magnetic dynamo. Our results have many of the properties of the theoretically-proposed Tayler-Spruit dynamo mechanism, which strongly enhances transport of angular momentum in radiative zones. It generates deep toroidal fields that are screened by the stellar outer layers. This mechanism could produce strong magnetic fields inside radiative stars, without an observable field on their surface.

References in corpus (5)

• Slowing the Spins of Stellar Cores
• On magnetic instabilities and dynamo action in stellar radiation zones
• Magnetic massive stars as progenitors of "heavy" stellar-mass black holes
• 3D evolution of magnetic fields in a differentially rotating stellar radiative zone
• Magnetic fields driven by tidal mixing in radiative stars

Cited by in corpus (20)

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• Tayler-Spruit dynamo in stably stratified rotating fluids: Application to proto-magnetars
• Unveiling complex magnetic field configurations in red giant stars
• Constraints on the properties of macroscopic transport in the Sun from combined lithium and beryllium depletion
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• Shaping core dynamos in A-type stars: The role of dipolar fossil fields
• Gravity's role in taming the Tayler instability in red giant cores
• Exploring the probing power of gamma-Dor's inertial dip for core magnetism: case of a toroidal field
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