Free Access

Fig. 2


Mean longitudinal magnetic field (top) and mean magnetic field modulus (bottom) of HD 18078 against rotation phase. In the top panel the different symbols distinguish observations obtained in three different consecutive cycles (in order, filled dots, open circles, and filled triangles). In the bottom panel, open squares correspond to observations obtained with AURELIE, filled squares to KPNO coudé spectra, and filled triangles to GECKO data. The two open triangles pointing downwards identify upper limit estimates from AURELIE spectra in which the Fe iiλ 6149.2 line is not magnetically resolved (see text). The short-dashed lines are the best fits of the observations by a cosine wave (for B) and by a cosine wave and its first harmonic (for Bz). The long-dashed lines show the variations of the two considered field moments that are predicted by the simple model discussed in Sect. 4.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.