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arXiv · 2207.08526

Asteroseismology reveals the near-core magnetic field strength in the early-B star HD 43317

D. M. Bowman·D. Lecoanet·T. Van Reeth
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Abstract

Spectropolarimetic campaigns have established that large-scale magnetic fields are present at the surfaces of approximately 10% of massive dwarf stars. However, there is a dearth of magnetic field measurements for their deep interiors. Asteroseismology of gravity-mode pulsations combined with rotating magneto-hydrodynamical calculations of the early-B main-sequence star HD 43317 constrain its magnetic field strength to be approximately $5\times10^{5}$ G just outside its convective core. This proof-of-concept study for magneto-asteroseismology opens a new window into the observational characterisation of magnetic fields inside massive stars.

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D. M. Bowman, D. Lecoanet, T. Van Reeth. 2022-07-18. Asteroseismology reveals the near-core magnetic field strength in the early-B star HD 43317. https://doi.org/10.1017/s174392132200268x

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