Nearly-uniform internal rotation of solar-like main-sequence stars revealed by space-based asteroseismology and spectroscopic measurements

TL;DR

This study combines asteroseismology and spectroscopy to show that solar-like main-sequence stars generally have nearly uniform internal rotation, indicating efficient angular momentum transport during their evolution.

Contribution

It provides the first comprehensive analysis of internal rotation profiles in main-sequence stars using space-based asteroseismology and spectroscopy, revealing near-uniform rotation.

Findings

Most stars show small differences between surface and interior rotation rates.

The rotation rate difference between convective and radiative zones is within a factor of two.

Efficient angular momentum transport occurs during or before the main-sequence phase.

Abstract

The rotation rates in the deep interior and at the surface of 22 main-sequence stars with masses between $1.0$ and $1.6\,{\rm M}_{\odot}$ are constrained by combining asteroseismological analysis with spectroscopic measurements. The asteroseismic data of each star are taken by the {\it Kepler} or CoRoT space mission. It is found that the difference between the surface rotation rate and the average rotation rate (excluding the convective core) of most of stars is small enough to suggest that an efficient process of angular momentum transport operates during and/or before the main-sequence stage of stars. If each of the surface convective zone and the underlying radiative zone, for individual stars, is assumed to rotate uniformly, the difference in the rotation rate between the two zones turns out to be no more than a factor of two in most of the stars independently of their ages.