Related papers: Element stratification in main sequence stars and …
The observational evidence that planetary systems can be very different from each other, suggests that their dynamical histories were very diverse, probably as a result of a strong sensitivity to the initial conditions. Severe dynamical…
Sudden changes in the internal structure of stars, placed at the interface between convective and radiative regions, regions of partial ionisation, or between layers that have acquired different chemical composition as a result of nuclear…
The possibility of measuring the internal rotation of the Sun and stars thanks to helio- and asteroseismology offers tremendous constraints on hydro- and magnetohydrodynamical processes acting in stellar interiors. Understanding the…
The large separations between the oscillation frequencies of solar-like stars are measures of stellar mean density. The separations have been thought to be mostly constant in the observed range of frequencies. However, detailed…
The influence of rotational mixing on the evolution and asteroseismic properties of solar-type stars is studied. Rotational mixing changes the global properties of a solar-type star with a significant increase of the effective temperature…
Massive stars are linked with diverse astronomical processes and objects including star formation, supernovae and their remnants, cosmic rays, interstellar media, and galaxy evolution. Understanding their properties is of primary importance…
Multiple systems play an important role in the evolution of star clusters. First we discuss several formation mechanisms which depend on the presence of binaries, either primordial or of dynamical origin. Hierarchical configurations are…
Massive stars are important metal factories in the Universe. They have short and energetic lives, and many of them inevitably explode as a supernova and become a neutron star or black hole. In turn, the formation, evolution and explosive…
The stars of the middle main sequence have relatively quiescent outer layers, and unusual chemical abundance patterns may develop in their atmospheres. The presence of chemical peculiarities reveal the action of such subsurface phenomena as…
We show that element diffusion can produce large fluctuations in the initial helium abundance of the star-forming clouds. Diffusion time-scale, which in stars is much larger than the Hubble time, can fall below 10^8 years in the neutral gas…
The study of stellar oscillations - asteroseismology - has revolutionized our understanding of the physical properties of the Sun, and similar potential for other stars has been demonstrated in recent years. In particular, asteroseismic…
New insights on stellar evolution and stellar interior physics are being made possible by asteroseismology, the study of stars by the observation of their natural, resonant oscillations. Asteroseismology is making significant contributions…
The evolution of strange mode instabilities into the non linear regime has been followed by numerical simulation for an envelope model of a massive star having solar chemical composition, M=50M_sun, T_eff=10^4K and L=1.17*10^6 L_sun.…
At very low metallicity, the effects of differential rotation have a more important impact on the evolution of stars than at high metallicity. Rotational mixing leads to the production of great quantities of helium and of primary $^{14}$N…
Almost 100 years ago Sir Arthur Eddington noted that the interiors of stars were inaccessible to observations. The advent of helio- and asteroseismology has completely changed this assessment. Helioseismology has provided very detailed…
The first massive stars triggered the onset of chemical evolution by releasing the first metals (elements heavier than helium) in the Universe. The nature of these stars and how the early chemical enrichment took place is still largely…
Oscillations occur in stars of most masses and essentially all stages of evolution. Asteroseismology is the study of the frequencies and other properties of stellar oscillations, from which we can extract fundamental parameters such as…
Main sequence stars hosting extreme quantities of inner planetary system debris are likely experiencing transient dust production events. The nature of these events, if they can be unambiguously attributed to a single process, can…
The region in the HR-diagram where the main sequence intersects the classical instability strip hosts A- and F-type stars exhibiting a rich variety of physical phenomena, such as pulsations on various time scales and chemical peculiarities.…
The richness and very high accuracy of the observed frequencies of solar oscillations provide tight constraints on the structure of the solar interior and hence on the assumptions underlying the calculation of solar models. This permits the…