Browse by author
Lookup NU author(s): Rathish Ratnasingam, Dr Philipp EdelmannORCiD, Dr Dominic BowmanORCiD, Professor Tamara Rogers
This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).
© 2024. The Author(s). Published by the American Astronomical Society. It is well-known that the cores of massive stars sustain a stellar dynamo with a complex magnetic field configuration. However, the same cannot be said for the field's strength and geometry at the convective-radiative boundary, which are crucial when performing asteroseismic inference. In this Letter, we present 3D magnetohydrodynamic (MHD) simulations of a 7 M⊙ mid-main-sequence star, with particular attention given to the convective-radiative boundary in the near-core region. Our simulations reveal that the toroidal magnetic field is significantly stronger than the poloidal field in this region, contrary to recent assumptions. Moreover, the rotational shear layer, also important for asteroseismic inference, is specifically confined within the extent of the Brunt-Väisälä frequency peak. These results, which are based on the inferred properties of HD 43317, have widespread implications for asteroseismic studies of rotation, mixing, and magnetism in stars. While we expect our results to be broadly applicable across stars with similar Brunt-Väisälä frequency profiles and stellar masses, we also expect the MHD parameters (e.g., Rem) and the initial stellar rotation rate to impact the geometry of the field and differential rotation at the convective-radiative interface.
Author(s): Ratnasingam RP, Edelmann PVF, Bowman DM, Rogers TM
Publication type: Article
Publication status: Published
Journal: Astrophysical Journal Letters
Year: 2024
Volume: 977
Issue: 1
Online publication date: 10/12/2024
Acceptance date: 20/11/2024
Date deposited: 06/01/2025
ISSN (print): 2041-8205
ISSN (electronic): 2041-8213
Publisher: American Astronomical Society
URL: https://doi.org/10.3847/2041-8213/ad95f8
DOI: 10.3847/2041-8213/ad95f8
Altmetrics provided by Altmetric
