English
Related papers

Related papers: Empirical Constraints on Convective Core Overshoot

200 papers

Stellar models generally use simple parametrizations to treat convection. The most widely used parametrization is the so-called "Mixing Length Theory" where the convective eddy sizes are described using a single number, \alpha, the…

We briefly review the main problems related to the computation of the evolution of intermediate-mass stars: the treatment of turbulent convection and the occurrence of blue loops during the core He-burning phase. It is shown that, in order…

Astrophysics · Physics 2007-05-23 S. Cassisi

Most current models of low mass red giant stars do not reproduce the observed position of the red giant branch luminosity bump, a diagnostic of the maximum extent of the convective envelope during the first dredge up. Global asteroseismic…

Solar and Stellar Astrophysics · Physics 2023-04-17 Christopher J. Lindsay , J. M. Joel Ong , Sarbani Basu

(abridged) Context: Rotation is thought to influence the size of convective eddies and the efficiency of convective energy transport in the deep convection zones of stars. Rotationally constrained convection has been invoked to explain the…

Solar and Stellar Astrophysics · Physics 2023-10-20 Petri J. Käpylä

Low-mass models of M-dwarfs that undergo the convective kissing instability fluctuate in luminosity and temperature resulting in a gap in the main sequence that is observed in the $Gaia$ data. During this instability, the models have…

Solar and Stellar Astrophysics · Physics 2023-09-15 Santana Mansfield , Pavel Kroupa

This work concerns the study of the properties of convective cores in main-sequence models of solar-like pulsators and what information they may hold about stellar ages. We verified that the maximum absolute frequency derivative of…

Solar and Stellar Astrophysics · Physics 2014-01-10 I. M. Brandão , M. S. Cunha , J Christensen-Dalsgaard

We compute rotating 1D stellar evolution models that include a modified temperature gradient in convection zones and criterion for convective instability inspired by rotating 3D hydrodynamical simulations performed with the MUSIC code. In…

Solar and Stellar Astrophysics · Physics 2021-10-27 Thomas Constantino , Isabelle Baraffe , Thomas Goffrey , Jane Pratt , Thomas Guillet , Dimitar Vlaykov , Louis Amard

Recent structure models of Jupiter suggest the existence of an extended region in the deep interior with a high heavy element abundance, referred to as a dilute core. This finding has led to increased interest in modelling the formation and…

Earth and Planetary Astrophysics · Physics 2024-12-02 Jesse Polman , Christoph Mordasini

We study a process of slow mixing in stars with convective envelopes, which is driven by the settling of cool downward plumes below the base of the convection zone. If a small fraction (of order $10^{-7}$) of the material cooled at the…

Solar and Stellar Astrophysics · Physics 2015-06-17 R. Andrássy , H. C. Spruit

The binary star alpha Aurigae (otherwise known as Capella) is extremely important to understand the core hydrogen and helium burning phases of the stars, as the primary star is likely evolving through the core helium burning phase, and the…

Solar and Stellar Astrophysics · Physics 2023-08-09 E. Marini , C. Ventura , M. Tailo , P. Ventura , F. Dell'Agli , M. Castellani

We give a brief review on the properties of asymptotic giant branch models with overshoot. Then we describe new model calculations with overshoot. Initial masses are ranging from 1 to 3Msun and metallicities are Z=0.02, 0.01 and 0.001.…

Astrophysics · Physics 2007-05-23 Falk Herwig , Thomas Bloecker , Thomas Driebe

We carry out high resolution calculations of the solar overshoot region with unprecedentedly realistic parameters, especially the small energy flux compared with $\rho c^3_\mathrm{s}$, where $\rho$ and $c_\mathrm{s}$ are density and speed…

Solar and Stellar Astrophysics · Physics 2017-07-19 H. Hotta

Magnetic fields are hypothesized to inflate the radii of low-mass stars---defined as less massive than 0.8$M_\odot$---in detached eclipsing binaries (DEBs). We investigate this hypothesis using the recently introduced magnetic Dartmouth…

Solar and Stellar Astrophysics · Physics 2013-12-09 Gregory A. Feiden , Brian Chaboyer

Stellar convection is customarily described by Mixing-Length Theory, which makes use of the mixing-length scale to express the convective flux, velocity, and temperature gradients of the convective elements and stellar medium. The…

Solar and Stellar Astrophysics · Physics 2015-06-19 S. Pasetto , C. Chiosi , M. Cropper , E. K. Grebel

The detection of mixed oscillation modes offers a unique insight into the internal structure of core helium burning (CHeB) stars. The stellar structure during CHeB is very uncertain because the growth of the convective core, and/or the…

Solar and Stellar Astrophysics · Physics 2015-07-06 Thomas Constantino , Simon W. Campbell , Joergen Christensen-Dalsgaard , John C. Lattanzio , Dennis Stello

With the greater power to infer the state of stellar interiors provided by asteroseismology, it has become possible to study the survival of initially convective cores within stars during their main-sequence evolution. Standard theories of…

Solar and Stellar Astrophysics · Physics 2023-06-16 Mark Lykke Winther , Víctor Aguirre Børsen-Koch , Jakob Lysgaard Rørsted , Amalie Stokholm , Kuldeep Verma

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 a theoretical description of macroscopic diffusion caused by convective overshoot in pure-hydrogen DA white dwarfs using three-dimensional (3D), closed-bottom, radiation hydrodynamics CO$^5$BOLD simulations. We rely on a new grid…

Solar and Stellar Astrophysics · Physics 2019-07-10 Tim Cunningham , Pier-Emmanuel Tremblay , Bernd Freytag , Hans-Günther Ludwig , Detlev Koester

The Sch\"onberg-Chandrasekhar (SC) limit is a well-established result in the understanding of stellar evolution. It provides an estimate of the point at which an evolved isothermal core embedded in an extended envelope begins to contract.…

Solar and Stellar Astrophysics · Physics 2015-06-03 Warrick H. Ball , Christopher A. Tout , Anna N. Żytkow

The red-giant branch bump provides valuable information for the investigation of the internal structure of low-mass stars. Because current models are unable to accurately predict the occurrence and efficiency of mixing processes beyond…

Solar and Stellar Astrophysics · Physics 2018-06-27 Saniya Khan , Oliver J. Hall , Andrea Miglio , Guy R. Davies , Benoît Mosser , Léo Girardi , Josefina Montalbán