Related papers: Angular-momentum coupling through the tachocline
Angular momentum transport must have occurred in the Sun's radiative zone to explain its current solid body rotation. We survey the stability of the early Sun's radiative zone with respect to diffusive rotational instabilities, for a…
The Sun's axisymmetric large-scale flows, differential rotation and meridional circulation, are thought to be maintained by the influence of rotation on the thermal-convective motions in the solar convection zone. These large-scale flows…
The tachocline is believed to be the region where the solar dynamo operates. With over a solar cycle's worth of data available from the MDI and GONG instruments, we are in a position to investigate not merely the average structure of the…
The purpose of this paper is to improve the modeling of the mixing of chemical elements that occurs in stellar radiation zones. In addition to the classical rotational mixing considered in our previous paper, which results of the combined…
The internal rotation and magnetism of evolved massive stars are considered in response to i) the inward pumping of angular momentum through deep and slowly rotating convective layers; and ii) the winding up of a helical magnetic field in…
Whenever stars are rotating very fast (Omega/Omega_crit > 0.7, with Omega_crit the Keplerian angular velocity of the star accounting for its deformation) radiative stellar winds are enhanced in polar regions. This theoretical prediction is…
The rotation rate of the solar radiative zone is an important diagnostic for angular-momentum transport in the tachocline and below. In this paper we study the contribution of viscous and magnetic stresses to the global angular-momentum…
The angular momentum of a star is an important astrophysical quantity related to its internal structure, formation and evolution. On average, helioseismology yields S = 1.92 10^41 kg m^2 s^-1 for the angular momentum of the Sun. We show how…
Recent asteroseismic studies have revealed that the convective core of $\gamma$ Doradus stars rotates faster than their radiative interior. We study the development of differential rotation near the convective core to test angular momentum…
Angular momentum balance is examined in the context of the electrodynamics of a spinning charged sphere, which is allowed to possess any variable angular velocity. We calculate the electric and magnetic fields of the (hollow) sphere, and…
Stellar winds are thought to be the main process responsible for the spin down of main-sequence stars. The extraction of angular momentum by a magnetized wind has been studied for decades, leading to several formulations for the resulting…
The Sun's internal rotation {\Omega}(r,{\Theta}) has previously been measured using helioseismology techniques and found to be a complex function of co-latitude, {\theta}, and radius, r. From helioseismology and observations of apparently…
Stellar tachoclines are thin regions located between the radiative core and the convective envelope of solar-type stars. They are defined as layers where the rotation of the radiative interior transitions to the differential rotation of the…
Helioseismology has allowed us to infer the rotation in the greater part of the solar interior with high precision and resolution. The results show interesting conflicts with earlier theoretical expectations, indicating that the the Sun is…
In the outer envelope of the Sun and in other stars, differential rotation and meridional circulation are maintained via the redistribution of momentum and energy by convective motions. In order to properly capture such processes in a…
A prerequisite for the formation of stars and planetary systems is that angular momentum is transported in some way from the inner regions of the accretion disc. Tidal effects may play an important part in this angular momentum transport.…
With the first light of COROT, the preparation of KEPLER and the future helioseismology spatial projects such as GOLF-NG, a coherent picture of the evolution of rotating stars from their birth to their death is needed. We describe here the…
When they first appear in the HR diagram, young stars rotate at a mere 10\% of their break-up velocity. They must have lost most of the angular momentum initially contained in the parental cloud, the so-called angular momentum problem. We…
We discuss how recent advances in observations, theory and numerical simulations have allowed the stellar community to progress in its understanding of stellar convection, rotation and magnetism and to assess the degree to which the Sun and…
Transport of angular momentum has been a challenging topic within the stellar evolution community, even more since the recent asteroseismic surveys. All published studies on rotation using asteroseismic observations show a discrepancy…