2009/04/29 by M. Godart, A. Noels, M.‐A. Dupret +2
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Atomic physics #Convection #Excited state #Mechanics #Opacity #Optics #Physics #Radiative transfer #Red supergiant #Stars #Stellar pulsation #Stellar, planetary, and galactic studies #Supergiant #astro-ph.SR
paper · pdf · doi:10.1111/j.1365-2966.2009.14903.x
9 pages, 11 figures, accepted for publication in MNRAS
arxiv created 2009/04/29 · openalex publication_date 2009/06/05 · arxiv updated 2015/05/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Thanks to their past history on the main-sequence phase, supergiant massive stars develop a convective shell around the helium core. This intermediate convective zone (ICZ) plays an essential role in governing which g-modes are excited. Indeed, a strong radiative damping occurs in the high-density radiative core but the ICZ acts as a barrier preventing the propagation of some g-modes into the core. These g-modes can thus be excited in supergiant stars by the κ-mechanism in the superficial layers due to the opacity bump of iron, at log T= 5.2. However, massive stars are submitted to various complex phenomena such as rotation, magnetic fields, semiconvection, mass loss, overshooting. Each of these phenomena exerts a significant effect on the evolution and some of them could prevent the onset of the convective zone. We develop a numerical method which allows us to select the reflected, thus the potentially excited, modes only. We study different cases in order to show that mass loss and overshooting, in a large enough amount, reduce the extent of the ICZ and are unfavourable to the excitation of g-modes.