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

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Context: We study the impact of two-dimensional spherical shells on compressible convection. Realistic profiles for density and temperature from a one-dimensional stellar evolution code are used to produce a model of a large stellar…

Solar and Stellar Astrophysics · Physics 2016-10-05 J. Pratt , I. Baraffe , T. Goffrey , C. Geroux , M. Viallet , D. Folini , T. Constantino , M. Popov , R. Walder

Stellar evolution codes play a major role in present-day astrophysics, yet they share common simplifications related to the outer layers of stars. We seek to improve on this by the use of results from realistic and highly detailed 3D…

Convective overshoot mixing is a critical ingredient of stellar structure models, but is treated in most cases by ad hoc extensions of the mixing-length theory for convection. Advanced theories which are both more physical and numerically…

Solar and Stellar Astrophysics · Physics 2022-11-16 Felix Ahlborn , Friedrich Kupka , Achim Weiss , Martin Flaskamp

In this contribution we present initial results of a study on convective boundary mixing (CBM) in massive stellar models using the GENEVA stellar evolution code. Before undertaking costly 3D hydrodynamic simulations, it is important to…

Solar and Stellar Astrophysics · Physics 2015-06-23 Andrea Cristini , Raphael Hirschi , Cyril Georgy , Casey Meakin , David Arnett , Maxime Viallet

We present the first detailed three-dimensional (3D) hydrodynamic implicit large eddy simulations of turbulent convection of carbon burning in massive stars. Simulations begin with radial profiles mapped from a carbon burning shell within a…

Solar and Stellar Astrophysics · Physics 2017-08-02 Andrea Cristini , Casey Meakin , Raphael Hirschi , David Arnett , Cyril Georgy , Maxime Viallet

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

1D and 2D supernova simulations for stars between 11 and 25 solar masses are presented, making use of the Prometheus/Vertex neutrino-hydrodynamics code, which employs a full spectral treatment of the neutrino transport. Multi-dimensional…

Astrophysics · Physics 2009-11-11 R. Buras , H. -Th. Janka , M. Rampp , K. Kifonidis

Convective cores are the hydrogen reservoirs of main sequence stars that are more massive than around 1.2 solar masses. The characteristics of the cores have a strong impact on the evolution and structure of the star. However, such results…

Solar and Stellar Astrophysics · Physics 2023-08-09 Anthony Noll , Sébastien Deheuvels

Non-spherical structure in massive stars at the point of iron core collapse can have a qualitative impact on the properties of the ensuing core-collapse supernova explosions and the multi-messenger signals they produce. Strong perturbations…

Solar and Stellar Astrophysics · Physics 2021-11-03 C. E. Fields , S. M. Couch

We present multidimensional modeling of convection and oscillations in main-sequence stars somewhat more massive than the Sun, using three separate approaches: 1) Using the 3-D planar StellarBox radiation hydrodynamics code to model the…

Solar and Stellar Astrophysics · Physics 2016-05-17 Joyce A. Guzik , T. H. Morgan , N. J. Nelson , C. Lovekin , K. Kosak , I. N. Kitiashvili , N. N. Mansour , A. Kosovichev

We perform Large eddy simulations of turbulent compressible convection in stellar-type convection zones by solving the Navi\'{e}r-Stokes equations in three dimensions. We estimate the extent of penetration into the stable layer above a…

Astrophysics · Physics 2009-06-23 Partha S. Pal , Harinder P. Singh , Kwing L. Chan , M. P. Srivastava

We construct a semi-analytical model that describes the convective core mass evolution of massive stars experiencing mass loss during the main-sequence stage. We first conduct a suite of 1D stellar evolution calculations to build insight…

Solar and Stellar Astrophysics · Physics 2024-09-04 Minori Shikauchi , Ryosuke Hirai , Ilya Mandel

Semiconvection - mixing that occurs in regions that are stable when considering compositional gradients, but unstable when ignoring them - is shown to have the greatest potential impact on main sequence stars with masses in the range 1.2 -…

Solar and Stellar Astrophysics · Physics 2016-01-27 Kevin Moore , Pascale Garaud

The atmospheres of cool main-sequence stars are structured by convective flows from the convective envelope that penetrate the optically thin layers and lead to structuring of the stellar atmospheres analogous to solar granulation. The…

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

We use the 3D stellar structure code DJEHUTY to model the ingestion of protons into the intershell convection zone of a 1 solar mass asymptotic giant branch star of metallicity Z=10^-4. We have run two simulations: a low resolution one of…

Solar and Stellar Astrophysics · Physics 2015-05-30 Richard J. Stancliffe , David S. P. Dearborn , John C. Lattanzio , Stuart A. Heap , Simon W. Campbell

Because Cepheid variable stars have long been used as a cosmic benchmark, the accuracy of stellar evolution models for Cepheids have wide-reaching effects. Our goal is to provide a detailed multi-dimensional picture of hydrodynamic…

Solar and Stellar Astrophysics · Physics 2025-06-25 Maxime Stuck , Jane Pratt , Isabelle Baraffe , Joyce Ann Guzik , Mary-Geer Dethero , Dimitar Vlaykov , Tom Goffrey , Arthur Le Saux

Some physical processes that occur during a star's main-sequence evolution also affect its post main-sequence evolution. It is well known that stars with masses above approximately 1.1 $M_{\odot}$ have well-mixed convective cores on the…

Solar and Stellar Astrophysics · Physics 2024-02-21 Christopher J. Lindsay , J. M. Joel Ong , Sarbani Basu

We present a detailed study of the small frequency separations as diagnostics of the mass of the convective core and evolutionary stage of solar-type stars. We demonstrate how the small separations can be combined to provide sensitive tests…

Astrophysics · Physics 2009-11-11 Anwesh Mazumdar , Sarbani Basu , Braxton L. Collier , Pierre Demarque

The advent of massively parallel supercomputing has begun to permit explicit 3--D simulations of turbulent convection occurring within the cores of early-type main sequence stars. Such studies should complement the stellar structure and…

Astrophysics · Physics 2007-05-23 Allan Sacha Brun , Matthew Browning , Juri Toomre

An attempt at understanding downward overshooting in the convective envelopes of post-main-sequence stars has been made on the basis of three-dimensional large-eddy simulations, using artificially modified OPAL opacity and taking into…

Solar and Stellar Astrophysics · Physics 2016-03-08 Chun-Lin Tian , Li-Cai Deng , Kwing-Lam Chan