All NPOI visibilities, except the 673 nm channel which is shown in Fig. 5. A different wavelength is shown in each panel, as indicated. The symbols correspond to different physical baselines, plusses for AC0-AE0 and crosses for AE0-AW0. The blue, green and red lines are the same star+ring models as in Fig. 5, and have ring diameters and widths of (5.5, 1.0), (3.0, 3.0) and (1.0, 4.5) respectively. The red filled circles correspond to the best binary model deduced in Sect. 3.2 and online Fig. 7.