English
Related papers

Related papers: Towards a self-consistent model of the convective …

200 papers

Context. The surface structures and dynamics of cool stars are characterized by the presence of convective motions and turbulent flows which shape the emergent spectrum. Aims. We used realistic three-dimensional radiative hydrodynamical…

Solar and Stellar Astrophysics · Physics 2018-03-14 A. Chiavassa , L. Casagrande , R. Collet , Z. Magic , L. Bigot , F. Thevenin , M. Asplund

We perform a calibration of the mixing length of convection in stellar structure models against realistic 3D radiation-coupled hydrodynamics (RHD) simulations of convection in stellar surface layers, determining the adiabat deep in…

Solar and Stellar Astrophysics · Physics 2015-06-23 Regner Trampedach , Robert F. Stein , Jørgen Christensen-Dalsgaard , Åke Nordlund , Martin Asplund

Continued progress in observational stellar astrophysics requires a deep understanding of the underlying convection dynamics. We present results of realistic 3D radiative hydrodynamic simulations of the outer layers of a moderate mass star…

Solar and Stellar Astrophysics · Physics 2016-04-27 Irina N. Kitiashvili , Alexander G. Kosovichev , Nagi N. Mansour , Alan A. Wray

The inner structure of core-helium burning (CHeB) stars remains uncertain due to the yet unknown nature of mixing at the boundary of their cores. Large convective cores beyond a bare Schwarzschild model are favoured both from theoretical…

Solar and Stellar Astrophysics · Physics 2023-11-21 Simon Blouin , Falk Herwig , Huaqing Mao , Pavel Denissenkov , Paul R. Woodward

Supermassive stars are Population III stars with masses exceeding $10^4\,M_{\odot}$ that could be the progenitors of the first supermassive black holes. Their interiors are in a regime where radiation pressure dominates the equation of…

Solar and Stellar Astrophysics · Physics 2023-03-29 Simon Blouin , Huaqing Mao , Tyrone E. Woods , Pavel Denissenkov , Paul R. Woodward , Falk Herwig

Stellar evolution models of massive stars are important for many areas of astrophysics, for example nucleosynthesis yields, supernova progenitor models and understanding physics under extreme conditions. Turbulence occurs in stars primarily…

Solar and Stellar Astrophysics · Physics 2016-03-23 Andréa Cristini , Casey Meakin , Raphael Hirschi , David Arnett , Cyril Georgy , Maxime Viallet

(Abridged) We describe the results of three-dimensional (3D) numerical simulations designed to study turbulent convection in the stellar interiors, and compare them to stellar mixing-length theory (MLT). Simulations in 2D are significantly…

Astrophysics · Physics 2011-02-11 Casey A. Meakin , David Arnett

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…

Solar and Stellar Astrophysics · Physics 2015-05-27 Jan-Torge Schindler , Elizabeth M. Green , W. David Arnett

During their main sequence evolution, massive stars can develop convective regions very close to their surface. These regions are caused by an opacity peak associated with iron ionization. Cantiello et al. (2009) found a possible connection…

Solar and Stellar Astrophysics · Physics 2011-08-26 Matteo Cantiello , Jonathan Braithwaite , Axel Brandenburg , Fabio Del Sordo , Petri Käpylä , Norbert Langer

Main sequence, solar-like stars (M < 1.5 Msun) have outer convective envelopes that are sufficiently thick to affect significantly their overall structure. The radii of these stars, in particular, are sensitive to the details of…

Solar and Stellar Astrophysics · Physics 2018-12-26 F. Spada , P. Demarque , S. Basu , J. D. Tanner

Shell convection driven by nuclear burning in a stellar core is a common hydrodynamic event in the evolution of many types of stars. We encounter and simulate this convection (i) in the helium core of a low-mass red giant during core helium…

Solar and Stellar Astrophysics · Physics 2015-05-27 Miroslav Mocak , Ewald Muller , Lionel Siess

Hydrodynamical simulations of stellar interactions require stable models of stars as initial conditions. Such initial models, however, are difficult to construct for giant stars because of the wide range in spatial scales of the hydrostatic…

Solar and Stellar Astrophysics · Physics 2017-02-22 Sebastian T. Ohlmann , Friedrich K. Roepke , Rüdiger Pakmor , Volker Springel

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

Context: Internal chemical mixing in intermediate- and high-mass stars represents an immense uncertainty in stellar evolution models.In addition to extending the main-sequence lifetime, chemical mixing also appreciably increases the mass of…

Solar and Stellar Astrophysics · Physics 2021-11-10 Cole Johnston

State-of-the-art one-dimensional (1D) stellar evolution codes rely on simplifying assumptions, such as mixing length theory, in order to describe superadiabatic convection. As a result, 1D stellar structure models do not correctly recover…

Solar and Stellar Astrophysics · Physics 2019-08-07 Andreas Christ Sølvsten Jørgensen , Achim Weiss

We present the first detailed three-dimensional hydrodynamic implicit large eddy simulations of turbulent convection for carbon burning. The simulations start with an initial radial profile mapped from a carbon burning shell within a 15…

Solar and Stellar Astrophysics · Physics 2017-12-20 Andrea Cristini , Casey Meakin , Raphael Hirschi , David Arnett , Cyril Georgy , Maxime Viallet

Broadening and asymmetry of spectral lines in slowly rotating late A-type stars provide evidence for high-amplitude convective motions. The properties of turbulence observed in the A-star atmospheres are not understood theoretically and…

Astrophysics · Physics 2015-06-24 O. Kochukhov , B. Freytag , N. Piskunov , M. Steffen

Aims: We investigate from a theoretical perspective if space asteroseismology can be used to distinguish between different thermal structures and shapes of the near-core mixing profiles for different types of coherent oscillation modes in…

Solar and Stellar Astrophysics · Physics 2019-08-20 Mathias Michielsen , May G. Pedersen , Kyle C. Augustson , Stéphane Mathis , Conny Aerts

One-dimensional (1D) stellar evolution models are widely used across various astrophysical fields, however they are still dominated by important uncertainties that deeply affect their predictive power. Among those, the merging of…

The overall evolution of low-mass stars is heavily influenced by the processes occurring in the stellar interior. In particular, mixing processes in convectively unstable zones and overshooting regions affect the resulting observables and…

Solar and Stellar Astrophysics · Physics 2015-05-27 V. Silva Aguirre , J. Ballot , A. M. Serenelli , A. Weiss