A coupled model of magnetic flux generation and transport in stars

TL;DR

This paper introduces a comprehensive model combining magnetic flux generation, emergence, and surface transport in cool stars, linking dynamo processes with observable magnetic features.

Contribution

It presents a novel integrated model that connects the dynamo-generated magnetic fields with surface flux transport in stars.

Findings

Successful simulation of magnetic flux evolution for the Sun.

Extension of the model to rapidly rotating stars.

Insights into magnetic activity patterns in stars.

Abstract

We present a combined model for magnetic field generation and transport in cool stars with outer convection zones. The mean toroidal magnetic field, which is generated by a cyclic thin-layer alpha-omega dynamo at the bottom of the convection zone is taken to determine the emergence probability of magnetic flux tubes in the photosphere. Following the nonlinear rise of the unstable thin flux tubes, emergence latitudes and tilt angles of bipolar magnetic regions are determined. These quantities are put into a surface flux transport model, which simulates the surface evolution of magnetic flux under the effects of large-scale flows and turbulent diffusion. First results are discussed for the case of the Sun and for more rapidly rotating solar-type stars.