Related papers: The evolution of single B-type stars with a large …
Magnetic fields at the surface of a few early-type stars have been directly detected. These fields have magnitudes between a few hundred G up to a few kG. In one case, evidence of magnetic braking has been found. We investigate the effects…
Here we present evolutionary models for a set of massive stars, introducing a new prescription for the mass-loss rate obtained from hydrodynamical calculations in which the wind velocity profile, $v(r)$, and the line-acceleration,…
Context: The surface properties of rotating stars can vary from pole to equator, resulting in anisotropic stellar winds which are not included in the currently available evolutionary models. Aims: We develop a formalism to describe the mass…
Stellar evolution models of massive stars are very sensitive to the adopted mass-loss scheme. The magnitude and evolution of mass-loss rates significantly affect the main sequence evolution, and the properties of post-main sequence objects,…
We have previously analysed the spectra of 135 early B-type stars in the LMC and found several groups of stars that have chemical compositions that conflict with the theory of rotational mixing. Here we extend this study to Galactic and SMC…
A major uncertainty in the theory of stellar evolution is the angular momentum distribution inside stars and its change during stellar life. We compose a sample of 67 stars in the core-hydrogen burning phase with a $\log\,g$ value from…
We investigate the rotational evolution of young stars through Monte Carlo simulations. We simulate 280,000 stars, each of which is assigned a mass, a rotational period, and a mass accretion rate. The mass accretion rate depends on mass and…
Fundamental parameters of a sample of 26 apparently slowly-rotating single early B-type stars in the solar neighbourhood are presented and compared to high-precision data from detached eclipsing binaries (DEBs). The data are used to discuss…
The angular momentum evolution of stars is crucial for understanding the formation and evolution of stars and star clusters. Using high-resolution magnetohydrodynamical (MHD) simulations of star formation in clouds with different physical…
We investigate a sample of 6 Herbig Ae/Be stars belonging to the Orion OB1 association, as well as 73 low mass objects, members of the $\sigma$ Orionis cluster, in order to explore the angular momentum evolution at early stages of…
Zero age main sequence models of uniformly rotating stars have been computed for ten masses between 1.625 and 8 M_\odot and 21 rotation rates from zero to nearly critical rotation. The surface shape is used to distinguish rotation rather…
We assess the importance of tidal evolution and its interplay with magnetic braking in the population of hot-Jupiter planetary systems. By minimizing the total mechanical energy of a given system under the constraint of stellar angular…
A sample of 97 galactic field Be stars were studied by taking into account the effects induced by the fast rotation on their fundamental parameters. All program stars were observed in the BCD spectrophotometric system in order to minimize…
Early-type stars have convective cores due to a steep temperature gradient produced by the CNO cycle. These cores can host dynamos, and the generated magnetic fields can be relevant to explain the magnetism observed in Ap/Bp stars. Our main…
Be stars are rapidly rotating B main sequence stars, which show line emission due to an outflowing disc. By studying the evolution of rotating single star models, we can assess their contribution to the observed Be star populations. We…
Investigating the apparent anomalies in lithium (Li) surface abundance observed in the Sun and young stellar globular clusters holds significant promise for advancing our understanding of the mechanisms influencing Li depletion. This study…
Rotation has a number of important effects on the evolution of stars. It decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes. We have adapted the Cambridge stellar…
During the first half of main-sequence lifetimes, the evolution of rotation and magnetic activity in solar-type stars appears to be strongly coupled. Recent observations suggest that rotation rates evolve much more slowly beyond middle-age,…
We study the evolution of stars that may be the progenitors of long-soft gamma-ray burst (GRBs) -- rotating naked helium stars presumed to have lost their envelopes to winds or companions. Our aim is to investigate the formation and…
Stellar evolution calculations have had great success reproducing the observed atmospheric properties of different classes of stars. Recent detections of g-mode pulsations in evolved He burning stars allow a rare comparison of their…