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Related papers: Semi-convection: What is the underlying physical c…

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Hot luminous stars show a variety of phenomena in their photospheres and in their winds which still lack clear physical explanations at this time. Among these phenomena are non-thermal line broadening, line profile variability (LPVs),…

Solar and Stellar Astrophysics · Physics 2012-04-09 Matteo Cantiello , Jonathan Braithwaite , Axel Brandenburg , Fabio Del Sordo , Petri Käpylä , Norbert Langer

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

We study prospects for seismic sounding the layer of a partial mixing above the convective core in main-sequence stars with masses in the 1.2 -- 1.9 solar mass range. There is an initial tendency to an increase of convective core mass in…

Astrophysics · Physics 2007-05-23 B. L. Popielski , W. A. Dziembowski

The evolution of the first generations of stars at zero or extremly low metallicity, and especially some crucial properties like the primary N14 production, is charactarized by convective-reactive mixing events that are mostly absent from…

Astrophysics · Physics 2009-06-23 Paul Woodward , Falk Herwig , David Porter , Tyler Fuchs , Anthony Nowatzki , Marco Pignatari

Rotochemical heating originates in a departure from beta equilibrium due to spin-down compression in a rotating neutron star. The main consequence is that the star eventually arrives at a quasi-equilibrium state, in which the thermal photon…

Astrophysics · Physics 2011-07-19 Rodrigo Fernández , Andreas Reisenegger

A-type stars have a complex internal structure with the possibility of multiple convection zones. If not sufficiently separated, such zones will interact through the convectively stable regions that lie between them. It is therefore of…

Astrophysics · Physics 2009-11-13 L. J. Silvers , M. R. E. Proctor

We study the convection zones in the outer envelope of hot massive stars which are caused by opacity peaks associated with iron and helium ionization. We determine the occurrence and properties of these convection zones as function of the…

Solar and Stellar Astrophysics · Physics 2015-05-13 M. Cantiello , N. Langer , I. Brott , A. de Koter , S. N. Shore , J. S. Vink , A. Voegler , D. J. Lennon , S. -C. Yoon

Convection in the cores of massive stars becomes anisotropic when they rotate. This anisotropy leads to a misalignment of the thermal gradient and the thermal flux, which in turn results in baroclinicity and circulation currents in the…

Solar and Stellar Astrophysics · Physics 2018-10-26 Adam S. Jermyn , Christopher A. Tout , Shashikumar M. Chitre

Excitation of solar oscillations is attribued to turbulent motions in the solar convective zone. It is also currently believed that oscillations of low massive stars (M <2 Mo) - which possess an upper convective zone - are stochastically…

Astrophysics · Physics 2007-05-23 Reza Samadi

Convection plays a key role in the evolution of stars due to energy transport and mixing of composition. Despite its importance, this process is still not well understood. One longstanding conundrum in all 1D stellar evolution codes is the…

Solar and Stellar Astrophysics · Physics 2020-01-08 Etienne A. Kaiser , Raphael Hirschi , W. David Arnett , Andrea Cristini , Cyril Georgy , Laura J. A. Scott

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

Regions of stellar and planetary interiors that are unstable according to the Schwarzschild criterion, but stable according to the Ledoux criterion, are subject to a form of oscillatory double-diffusive (ODD) convection often called…

Solar and Stellar Astrophysics · Physics 2015-01-22 Toby S. Wood , Pascale Garaud , Stephan Stellmach

Although the dependence of convective core overshooting on mass has attracted much attention, no corresponding work exists for overshooting below a convective envelope. We aim to quantify this relationship for pre-main sequence stars of…

Solar and Stellar Astrophysics · Physics 2025-09-24 J. Pratt , I. Baraffe , M. -G. Dethero , M. Stuck , D. G. Vlaykov , T. Goffrey

Stars with very large mass loss on the red-giant branch can undergo the helium flash while descending the white-dwarf cooling curve. Under these conditions the flash convection zone will mix the hydrogen envelope with the hot helium-…

Astrophysics · Physics 2007-05-23 Allen V. Sweigart , Thomas M. Brown , Thierry Lanz , Wayne B. Landsman , Ivan Hubeny

Massive B type pulsators such as beta Cep and slowly pulsating B (SPB) stars pulsate due to layers of increased opacity caused by partial ionization. The increased opacity blocks the energy flux to the surface of the stars which causes the…

Astrophysics · Physics 2008-09-29 C. Karoff , T. Arentoft , L. Glowienka , C. Coutures , T. B. Nielsen , G. Dogan , F. Grundahl , H. Kjeldsen

Large regions of giant planets are thought to possess unstable thermal gradients stabilised by gradients in heavy-element composition. The fluid can then develop semi-convection, a double-diffusive instability driven by the unequal…

Fluid Dynamics · Physics 2026-05-27 Paul Pružina , Nathanaël Schaeffer , David Cébron

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

Many Sun-like stars are observed to host close-in super-Earths (SEs) as part of a multi-planetary system. In such a system, the spin of the SE evolves due to spin-orbit resonances and tidal dissipation. In the absence of tides, the planet's…

Earth and Planetary Astrophysics · Physics 2022-10-18 Yubo Su , Dong Lai

Observations indicate that the convective cores of stars must ingest a substantial amount of material from the overlying radiative zone, but the extent of this mixing and the mechanism which causes it remain uncertain. Recently, Anders et…

Solar and Stellar Astrophysics · Physics 2022-05-11 Adam S. Jermyn , Evan H. Anders , Daniel Lecoanet , Matteo Cantiello

Properties of semi-convection and core convective overshooting of stars with 15 $M_{\odot}$ and 30 $M_{\odot}$ are calculated in the present paper. New methods are used to deal with semi-convection. Different entropy gradient is used when…

Solar and Stellar Astrophysics · Physics 2015-06-18 Cai Yun Ding , Yan Li