Related papers: Stellar rotation: Evidence for a large horizontal …
Compression of the stellar winds from rapidly rotating hot stars is described by the wind compression model. However, it was also shown that rapid rotation leads to rotational distortion of the stellar surface, resulting in the appearance…
We derive the scaling of differential rotation in both slowly- and rapidly-rotating convection zones using order of magnitude methods. Our calculations apply across stars and fluid planets and all rotation rates, as well as to both…
Zahn (1975) first put forward and calculated in detail the torque experienced by stars in a close binary systems due to dynamical tides. His widely used formula for stars with radiative envelopes and convective cores is expressed in terms…
Dynamo action owing to helically forced turbulence and large-scale shear is studied using direct numerical simulations. The resulting magnetic field displays propagating wave-like behavior. This behavior can be modelled in terms of an…
Context. Mixing by convective overshooting has long been suggested to play an important role for the amount of hydrogen available to nuclear burning in convective cores of stars. The best way to model this effect is still debated. Aims. We…
It is becoming clear that `self--pollution' by the ejecta of massive asymptotic giant branch stars has an important role in the early chemical evolution of globular cluster stars, producing CNO abundance spreads which are observed also at…
This paper discusses the location of a sample of planetary nebulae on the HR diagram. We determine the internal velocity fields of 14 planetary nebulae from high-resolution echelle spectroscopy, with the help of photoionization models. The…
The rotation rates of six weakly-magnetic neutron stars accreting in low-mass X-ray binaries have most likely been measured by Type I X-ray burst observations with RXTE. The nearly coherent oscillations detected during the few seconds of…
We present the results of a set of N-body simulations following the long-term evolution of the rotational properties of star cluster models evolving in the external tidal field of their host galaxy, after an initial phase of violent…
We present the results of an ensemble of SPH simulations that follow the evolution of prestellar cores for $0.2\,{\rm Myr}$. All the cores have the same mass, and start with the same radius, density profile, thermal and turbulent energy.…
Massive stars exhibit a variety of instabilities, many of which are poorly understood. We explore instabilities induced by centrifugal forces and angular momentum transport in massive rotating stars. First, we derive and numerically solve…
(Abridged) Rotation has been shown to play a determinant role at very low metallicity, bringing heavy mass loss where almost none was expected. Is this still true when the metallicity strictly equals zero? The aim of our study is to get an…
Turbulence and magnetic fields are components of the interstellar medium and are interconnected through plasma processes. In particular, the magnetic flux transport in the presence of magneto-hydrodynamic (MHD) turbulence is an essential…
The main instabilities induced by rotation in stellar interiors are described. We derive from first principles the general equation describing the transport of the angular momentum. The case of the transport of the chemical species is also…
Mass loss due to line-driven winds is central to our understanding of the evolution of massive stars. We extend the evolution models introduced in Paper I, where the mass loss recipe is based on the simultaneous calculation of the wind…
The high end of the stellar mass function of galaxies is observed to have little evolution since z~1. This represents a stringent constraint for merger--based models, aimed at explaining the evolution of the most massive galaxies in the…
Two competing models, gravitational instability-driven transport and stellar feedback, have been proposed to interpret the high velocity dispersions observed in high-redshift galaxies. We study the major mechanisms to drive the turbulence…
Since 1995, more than 1500 exoplanets have been discovered around a large diversity of host stars (from M- to A-type stars). Tidal dissipation in stellar convective envelopes is a key actor that shapes the orbital architecture of…
The turbulent diffusion tensor describing the evolution of the mean concentration of a passive scalar is investigated for non-helically forced turbulence in the presence of rotation or a magnetic field. With rotation, the Coriolis force…
Turbulence can transport angular momentum in protoplanetary disks and influence the growth and evolution of planets. With spatially and spectrally resolved molecular emission line measurements provided by (sub)millimeter interferometric…