Related papers: Overshooting
The influence of extended convective mixing (overshoot) on asymptotic giant branch stellar evolution is investigated in detail. The extended mixing is treated time-dependently, and the efficiency declines exponentially with the geometric…
Overshooting and semiconvection are among the most uncertainties in the evolution of massive stars. Complete mixing over a certain distance beyond the convective boundary (Stothers \& Chin 1985) and an exponentially decaying diffusion…
Based on the turbulent convection model (TCM) of Li & Yang (2007), we have studied the characteristics of turbulent convection in the envelopes of 2 and 5M stars at the RGB and AGB phases. The TCM has been applied successfully in the whole…
For more than thirty years, the dynamical maintenance of the thin solar tachocline has remained one of the central outstanding problems of stellar astrophysics. Three main theories have been developed to explain the tachocline's thinness,…
The solar convection zone exhibits a strong level of differential rotation, whereby the rotation period of the polar regions is about 25-30% longer than the equatorial regions. The Coriolis force associated with these zonal flows…
The concept of overshoot has already been considered for numerous cases in stellar evolution calculations. We explore the consequences of overshoot at the convection zone which forms during the He-flash (thermal pulse) in AGB stars. We find…
Hot luminous stars show a variety of phenomena in their photospheres and winds which still lack clear physical explanation. Among these phenomena are photospheric turbulence, line profile variability (LPV), non-thermal emission, non-radial…
In previous work, we have shown that recent updated standard solar models cannot reproduce the radial profile of the sound speed at the base of the convective zone (CZ) and fail to predict the Li7 depletion. In parallel, helioseismology has…
The nonlinear coupling between stellar convection and rotation is of great interest because it relates to understanding both stellar evolution and activity. We investigated the influence of rotation and the Coriolis force on the dynamics…
The near-surface layers of cool main-sequence stars are structured by convective flows, which are overshooting into the atmosphere. The flows and the associated spatio-temporal variations of density and temperature affect spectral line…
We have investigated the role of the convective overshooting on the production of s-nuclei during core He-burning phase in stellar models with different initial mass and metallicity ($15 \leq M_{ZAMS}/M_{\odot} \leq 25$; $10^{-4} \leq Z…
In this paper, we present a model for the effects of the tachocline on the differential rotation in the solar convection zone. The mathematical technique relies on the assumption that entropy is nearly constant ("well-mixed") in isorotation…
Element settling inside the Sun now becomes detectable from the comparison of the observed oscillation modes with the results of the theoretical models. This settling is due, not only to gravitation, but also to thermal diffusion and…
A monomodal model for stellar and planetary convection is derived for the magnitude of the rms velocity, degree of superadiabaticity, and characteristic length scale as a function of rotation rate as well as with thermal and viscous…
A turbulent transport of radiation in the solar convective zone is investigated. The mean-field equation for the irradiation intensity is derived. It is shown that due to the turbulent effects, the effective penetration length of radiation…
We study the combined effects of convection and radiative diffusion on the evolution of thin magnetic flux tubes in the solar interior. Radiative diffusion is the primary supplier of heat to convective motions in the lower convection zone,…
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…
Convective boundary mixing (CBM) is ubiquitous in stellar evolution. It is a necessary ingredient in the models in order to match observational constraints from clusters, binaries and single stars alike. We compute `effective overshoot'…
We report the physical origin of transient off-centre convective zones (oCZs) that arise in mass accreting stellar models. Using detailed MESA simulations of binary evolution, we find that these oCZs are not numerical artefacts but emerge…
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…