Differential rotation in main-sequence solar-like stars: Qualitative inference from asteroseismic data

TL;DR

This study uses asteroseismology to qualitatively analyze differential rotation profiles in Sun-like stars, highlighting limitations in distinguishing detailed radial profiles but promising insights into latitudinal differential rotation and its solar-like or anti-solar-like nature.

Contribution

It introduces a forward modeling approach to assess the potential of asteroseismology for inferring differential rotation profiles in Sun-like stars, emphasizing qualitative constraints.

Findings

Asteroseismology cannot unambiguously distinguish between different radial rotation profiles.

Frequency splittings are more promising for measuring latitudinal differential rotation.

It may be possible to determine if the differential rotation is solar-like or anti-solar-like.

Abstract

Understanding differential rotation of Sun-like stars is of great importance for insight into the angular momentum transport in these stars. One means of gaining such information is that of asteroseismology. By a forward modeling approach we analyze in a qualitative manner the impact of different differential rotation profiles on the splittings of p-mode oscillation frequencies. The optimum modes for inference on differential rotation are identified along with the best value of the stellar inclination angle. We find that in general it is not likely that asteroseismology can be used to make an unambiguous distinction between a rotation profile such as, e.g., a conical Sun-like profile and a cylindrical profile. In addition, it seems unlikely that asteroseismology of Sun-like stars will result in inferences on the radial profile of the differential rotation, such as can be done for, e.g., red giants. At best one could possibly obtain the sign of the radial differential rotation gradient. Measurements of the extent of the latitudinal differential from frequency splitting are, however, more promising. One very interesting aspect that could likely be tested from frequency splittings is whether the differential rotation is solar-like or anti-solar-like in nature, in the sense that a solar-like profile has an equator rotating faster than the poles.