Radial differential rotation vs surface differential rotation: investigation based on dynamo models

TL;DR

This study uses dynamo models to compare surface differential rotation measurements with known radial differential rotation, highlighting the challenges and differences in measuring stellar rotation profiles.

Contribution

It introduces a method to infer surface differential rotation from dynamo models and compares it with the actual radial differential rotation used in the models.

Findings

Surface differential rotation can be estimated from dynamo models using observational techniques.

There are notable differences between surface and radial differential rotation in stars.

The study highlights the limitations of current observational methods in measuring stellar differential rotation.

Abstract

Differential rotation plays a crucial role in the alpha-omega dynamo, and thus also in creation of magnetic fields in stars with convective outer envelopes. Still, measuring the radial differential rotation on stars is impossible with the current techniques, and even the measurement of surface differential rotation is difficult. In this work we investigate the surface differential rotation obtained from dynamo models using similar techniques as are used on observations, and compare the results with the known radial differential rotation used when creating the Dynamo model.