Building and Maintaining a Solar Tachocline through Convective Dynamo Action

Autor: Matilsky, Loren I., Toomre, Juri
Rok vydání: 2021
Předmět:
Druh dokumentu: Working Paper
DOI: 10.5281/zenodo.4750777
Popis: For more than thirty years, the dynamical maintenance of the thin solar tachocline has remained one of the central outstanding problems of stellar astrophysics. Three main theories have been developed to explain the tachocline's thinness, but so far none of them has been shown to work convincingly in the extreme parameter regime of the solar interior. Here, we present a rotating, 3D, spherical-shell simulation of a combined solar-like convection zone and radiative zone that achieves a tachocline built and maintained by convective dynamo action. Because of numerical constraints, the dynamo prevents the viscous spread of the tachocline instead of the Eddington-Sweet-time-scale radiative spread believed to occur in the Sun. Nonetheless, our simulation supports the scenario of tachocline confinement via the cyclic solar dynamo, and is the first time one of the main confinement scenarios has been realized in a global, 3D, spherical-shell geometry including nonlinear fluid motions and a self-consistently generated dynamo.
Comment: 6 pages, 5 figures; In the 20.5th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, edited by Scott J. Wolk
Databáze: arXiv