Reconstructed large-scale magnetic field map of HD 9986, in flattened polar view. From the left, the radial, azimuthal, and meridional components of the magnetic field vector are illustrated. Concentric circles represent different stellar latitudes: −30 °, +30 °, and +60 ° (dashed lines), as well as the equator (solid line). The radial ticks are located at the rotational phases when the observations were collected. The rotational phases are computed with Eq. (1) using the first observation of each individual epoch (see Appendix D, publicly available on Zenodo). The colour bar indicates the polarity and strength (in G) of the magnetic field. Indications of polarity reversals of the radial field have occurred in 2010.76 and 2017.76 epochs, and of the azimuthal field in 2023.09.