相关论文: The spin-up of contracting red supergiants

First, we review the main physical effects to be considered in the building of evolutionary models of rotating stars on the Upper Main-Sequence (MS). The internal rotation law evolves as a result of contraction and expansion, meridional…

The internal rotation of post-main sequence stars is investigated, in response to the convective pumping of angular momentum toward the stellar core, combined with a tight magnetic coupling between core and envelope. The spin evolution is…

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…

When the core hydrogen is exhausted during stellar evolution, the central region of a star contracts and the outer envelope expands and cools, giving rise to a red giant, in which convection occupies a large fraction of the star.…

Context. We need to understand the spin evolution of massive stars to compute their internal rotationally induced mixing processes, isolate effects of close binary evolution, and predict the rotation rates of white dwarfs, neutron stars and…

We wish to understand the processes that control the fluid flows of a gravitationally contracting and rotating star or giant planet. We consider a spherical shell containing an incompressible fluid that is slowly absorbed by the core so as…

We discuss the spin evolution of pulsars in the case where a superfluid component of the star is coupled to the observable crust on long, spindown timescales. The momentum transfer from the superfluid interior results in an apparent decay…

Models of rapidly rotating massive stars at low metallicities show significantly different evolution and higher metal yields compared to non-rotating stars. We estimate the spin-down time-scale of rapid rotating non-convective stars…

We study the evolution of six exoplanetary systems with the stellar evolutionary code MESA and conclude that they will likely spin-up the envelope of their parent stars on the red giant branch (RGB) or later on the asymptotic giant branch…

The spin-rotation of a planet arises from the accretion of angular momentum during its formation, but the details of this process are still unclear. In the solar system, the equatorial rotation velocities and spin angular momentum of the…

We summarize recent 2D MHD simulations of line-driven stellar winds from rotating hot-stars with a dipole magnetic field aligned to the star's rotation axis. For moderate to strong fields, much wind outflow is initially along closed…

We study the effects of rotation on the outer convective zones of massive stars. We examine the effects of rotation on the thermal gradient and on the Solberg--Hoiland term by analytical developments and by numerical models. Writing the…

(abridged) This paper aims at deciphering the dynamics of the envelope of a rotating star when some angular momentum loss due to mass loss is present. We especially wish to know when the spin-down flow forced by the mass loss supersedes the…

(Edited) Many fast rotator stars (rotation periods of < 2 days) are found in unresolved binaries with separations of tens of au. This correlation leads to the question of whether the formation of binary stars inherently produces fast…

Rotation and mass loss are crucially interlinked properties of massive stars, strongly affecting their evolution and ultimate fate. Massive stars rotating near their breakup limit shed mass centrifugally, creating Be stars with…

This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation…

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…

Surface convection is important for the presence of magnetic activity at stars. So far, this convection is thought to be a result of heating from below, where convection cells rise and break up. New models reveal that surface convection is…

In the course of the life of a massive star, wind-wind interaction can give rise to the formation of circumstellar nebulae which are both predicted and observed in the nature. We present generic model calculations to predict the properties…

In this paper, we report the potential detection of a nonmonotonic radial rotation profile in a low-mass lower-luminosity giant star. For most low- and intermediate-mass stars, the rotation on the main sequence seems to be close to rigid.…