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arXiv · 2010.07482

New observations of NGC 1624-2 reveal a complex magnetospheric structure and underlying surface magnetic geometry

A. David-Uraz·V. Petit·M. E. Shultz·A. W. Fullerton·C. Erba·Z. Keszthelyi·S. Seadrow·G. A. Wade
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Abstract

NGC 1624-2 is the most strongly magnetized O-type star known. Previous spectroscopic observations of this object in the ultraviolet provided evidence that it hosts a large and dense circumstellar magnetosphere. Follow-up observations obtained with the \textit{Hubble Space Telescope} not only confirm that previous inference, but also suggest that NGC 1624-2's magnetosphere has a complex structure. Furthermore, an expanded spectropolarimetric time series shows a potential departure from a dipolar magnetic field geometry, which could mean that the strongest field detected at the surface of an O-type star is also topologically complex. This result raises important questions regarding the origin and evolution of magnetic fields in massive stars.

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A. David-Uraz, V. Petit, M. E. Shultz, A. W. Fullerton, C. Erba, Z. Keszthelyi, S. Seadrow, G. A. Wade. 2020-10-15. New observations of NGC 1624-2 reveal a complex magnetospheric structure and underlying surface magnetic geometry. https://doi.org/10.1093/mnras%2Fstaa3768

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