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arXiv · 1910.14495

No evidence of a sudden change of spectral appearance or magnetic field strength of the O9.7V star HD 54879

G. A. Wade·S. Bagnulo·Z. Keszthelyi·C. P. Folsom·E. Alecian·N. Castro·A. David-Uraz·L. Fossati·V. Petit·M. E. Shultz·J. Sikora
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Abstract

It was recently claimed that the magnetic O-type star HD 54879 exhibits important radial velocity variability indicative of its presence in a spectroscopic binary. More remarkably, it was furthermore reported that the star underwent a short, sudden variation in spectral type and magnetic field. In this Letter we examine new Narval and ESPaDOnS data of this star in addition to the previously-published FORS2 data and conclude that both the reported velocity variations and the sudden spectral and magnetic changes are spurious.

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G. A. Wade, S. Bagnulo, Z. Keszthelyi, C. P. Folsom, E. Alecian, N. Castro, A. David-Uraz, L. Fossati, V. Petit, M. E. Shultz, J. Sikora. 2019-10-31. No evidence of a sudden change of spectral appearance or magnetic field strength of the O9.7V star HD 54879. https://doi.org/10.1093/mnrasl%2Fslz174

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