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Related papers: Convective Penetration in Early-Type Stars

200 papers

The main scope of this paper is to investigate the possible existence of a metallicity dependence of the overshooting from main sequence stars turbulent cores. We focus on objects with masses in the range ~2.5 Msol - ~25 Msol. Basically,…

Astrophysics · Physics 2009-11-07 D. Cordier , Y. Lebreton , M. -J. Goupil , T. Lejeune , J. -P. Beaulieu , F. Arenou

This work investigates the properties of convection in stars with particular emphasis on entrainment across the upper convective boundary (CB). Idealised simulations of turbulent convection in the O-burning shell of a massive star are…

Solar and Stellar Astrophysics · Physics 2016-11-03 Samuel Jones , Robert Andrassy , Stou Sandalski , Austin Davis , Paul Woodward , Falk Herwig

Convective boundary mixing is one of the major uncertainties in stellar evolution. In order to study its dependence on boundary properties and turbulence strength in a controlled way, we computed a series of 3D hydrodynamical simulations of…

Solar and Stellar Astrophysics · Physics 2019-02-13 A. Cristini , R. Hirschi , C. Meakin , D. Arnett , C. Georgy , I. Walkington

Stars with masses $\gtrsim 4 \times 10^{27}M_{\rm{moose}} \approx 1.1 M_\odot$ have core convection zones during their time on the main sequence. In these moosive stars, convection introduces many uncertainties in stellar modeling. In this…

We present 3-D hydrodynamical simulations of core convection with a stably stratified envelope of a \unit{25}{\Msun} star in the early phase of the main-sequence. We use the explicit gas-dynamics code \code{PPMstar} which tracks two fluids…

Solar and Stellar Astrophysics · Physics 2024-08-13 Huaqing Mao , Paul Woodward , Falk Herwig , Pavel A. Denissenkov , Simon Blouin , William Thompson , Benjamin McDermott

Results of evolutionary modelling of subdwarf B stars are presented. For the first time, we explore the core and near-core mixing in the subdwarf B stars using new algorithms available in the MESA code: the predictive mixing scheme and the…

Solar and Stellar Astrophysics · Physics 2021-04-21 J. Ostrowski , A. Baran , S. Sanjayan , S. K. Sahoo

Mixing in the convective core is quite uncertain in core helium burning stars. In order to explore the overshooting mixing beyond the convective core, we incorporated the $k$-$\omega$ proposed by Li (2012, 2017) into MESA, and investigated…

Solar and Stellar Astrophysics · Physics 2018-08-15 Yan Li , Xing-hao Chen , He-ran Xiong , Jun-jun Guo , Xue-fei Chen , Zhan-wen Han

Stellar rotation on the main sequence is a complex function of mass and age, displaying multiple regimes whose physical origin remains only partially understood. In particular, the connection between the diversity of observed rotation rates…

Solar and Stellar Astrophysics · Physics 2026-05-13 Ana Brito , Ilídio Lopes

Asteroseismology of non-radial pulsations in Hot B Subdwarfs (sdB stars) offers a unique view into the interior of core-helium-burning stars. Ground-based and space-borne high precision light curves allow for the analysis of pressure and…

Solar and Stellar Astrophysics · Physics 2017-11-08 J. -T. Schindler , Elizabeth M. Green , W. David Arnett

Understanding the physical properties of star-forming cores as mass reservoirs for protostars, and the impact of turbulence, is crucial in star formation studies. We implemented passive tracer particles in clump-scale numerical simulations…

Astrophysics of Galaxies · Physics 2025-01-08 Shingo Nozaki , Hajime Fukushima , Kazuki Tokuda , Masahiro N. Machida

We calculate the evolution of cloud cores embedded in different envelopes to investigate environmental effects on the mass accretion rate onto protostars. As the initial state, we neglect the magnetic field and cloud rotation, and adopt…

Solar and Stellar Astrophysics · Physics 2023-01-11 Shingo Nozaki , Masahiro N. Machida

We present the results of 3--D simulations of core convection within A-type stars of 2 solar masses, at a range of rotation rates. We consider the inner 30% by radius of such stars, thereby encompassing the convective core and some of the…

Astrophysics · Physics 2008-11-26 Matthew Browning , Allan Sacha Brun , Juri Toomre

We discuss the effect of chemical separation as matter freezes at the base of the ocean of an accreting neutron star, and the subsequent enrichment of the ocean in light elements and inward transport of heat through convective mixing. We…

Solar and Stellar Astrophysics · Physics 2015-06-22 Zach Medin , Andrew Cumming

We propose a methodological framework to perform forward asteroseismic modeling of stars with a convective core, based on gravity-mode oscillations. These probe the near-core region in the deep stellar interior. The modeling relies on a set…

Recent photometric observations of massive stars have identified a low-frequency power excess which appears as stochastic low-frequency variability in light curve observations. We present the oscillation properties of high resolution…

Solar and Stellar Astrophysics · Physics 2024-05-01 William Thompson , Falk Herwig , Paul R. Woodward , Huaqing Mao , Pavel Denissenkov , Dominic M. Bowman , Simon Blouin

Spectroscopic studies of Galactic O and B stars show that many stars with masses above 8 M$_{\odot}$ are observed in the HR diagram just beyond the Main-Sequence (MS) band predicted by stellar models computed with a moderate overshooting.…

The convective overshoot mixing plays an important role in stellar structure and evolution. However, the overshoot mixing is a long standing problem. The uncertainty of the overshoot mixing is one of the most uncertain factors in stellar…

Solar and Stellar Astrophysics · Physics 2013-07-16 Q. S. Zhang

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…

Solar and Stellar Astrophysics · Physics 2013-08-27 Benjamin Beeck , Robert H. Cameron , Ansgar Reiners , Manfred Schüssler

We present a model for the formation of massive ($M > 10 M_\odot$) stars through accretion-induced collisions in the cores of embedded dense stellar clusters. This model circumvents the problem of accreting onto a star whose luminosity is…

Astrophysics · Physics 2009-10-30 Ian A. Bonnell , Matthew R. Bate , Hans Zinnecker

The evolution of stars born with a convective core is highly dependent on the efficiency and extent of near core mixing processes, which effectively increases both the core mass and main-sequence lifetime. We investigate to what extent…

Solar and Stellar Astrophysics · Physics 2018-07-04 M. G. Pedersen , C. Aerts , P. I. Pápics , T. M. Rogers