Effects of stratification on overshooting and waves atop the convective core of M⊙ main-sequence stars

被引：1

作者：

Morison, A. ^{[1
]}

Le Saux, A. ^{[2
]}

Baraffe, I ^{[1
,3
]}

Morton, J. ^{[1
]}

Guillet, T. ^{[1
]}

Vlaykov, D. G. ^{[4
]}

Goffrey, T. ^{[5
,6
]}

Pratt, J. ^{[7
]}

机构：

[1] Univ Exeter, Phys & Astron, Exeter EX4 4QL, England

[2] Sorbonne Univ, Ecole Polytech, Ecole Normale Super, Lab Meteorol Dynam IPSL,CNRS, 4 Pl Jussieu, F-75231 Paris 05, France

[3] Univ Lyon, Ecole Normale Super Lyon, CRAL UMR CNRS 5574, F-69007 Lyon, France

[4] Univ Exeter, Math & Stat, Exeter EX4 4QF, England

[5] Univ Warwick, Ctr Fus Space & Astrophys, Dept Phys, Coventry CV4 7AL, England

[6] Univ Birmingham, Healthcare Technol Inst, Sch Chem Engn, Birmingham B15 2TT, England

[7] Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2024年 / 532卷 / 02期

基金：

英国科学技术设施理事会;

关键词：

asteroseismology; hydrodynamics; waves; software: simulations; stars: interiors; INTERNAL GRAVITY-WAVES; MASSIVE STARS; ANGULAR-MOMENTUM; 2-DIMENSIONAL SIMULATIONS; 3-DIMENSIONAL SIMULATIONS; PENETRATION; SOLAR; UNCERTAINTIES; GENERATION; LUMINOSITY;

D O I：

10.1093/mnras/stae1678

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

As a massive star evolves along the main sequence, its core contracts, leaving behind a stable stratification in helium. We simulate two-dimensional convection in the core at three different stages of evolution of a 5M(circle dot) star, with three different stratifications in helium atop the core. We study the propagation of internal gravity waves in the stably stratified envelope, along with the overshooting length of convective plumes above the convective boundary. We find that the stratification in helium in evolved stars hinders radial motions and effectively shields the radiative envelope against plume penetration. This prevents convective overshooting from being an efficient mixing process in the radiative envelope. In addition, internal gravity waves are less excited in evolved models compared to the zero-age-main-sequence model, and are also more damped in the stratified region above the core. As a result, the wave power is several orders of magnitude lower in mid- and terminal-main-sequence models compared to zero-age-main-sequence stars.

引用

页码：2778 / 2787

页数：10