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Context. HD 110432 was classified as a "\gamma Cas X-ray analog" since it hassimilar peculiar X-ray and optical characteristics, i.e. a hard-thermal X-rayvariable emission and an optical spectrum affected by an extensive disk. Lopesde Oliveira et al. (2007) suggest that it might be a Be star harboring anaccreting white dwarf or that the X-rays may come from an interaction betweenthe surface of the star and its disk. Aims. To investigate the disk around thisBe star we used the VLTI/AMBER instrument, which combines high spectral(R=12000) and high spatial (\theta min =4 mas) resolutions. Methods. Weconstrain the geometry and kinematics of its circumstellar disk from thehighest spatial resolution ever achieved on this star. Results. We obtain adisk extension in the Br{\gamma} line of 10.2 D\ast and 7.8 D\ast in the He Iline at 2.05 \mu m assuming a Gaussian disk model. The disk is clearlyfollowing a Keplerian rotation. We obtained an inclination angle of 55\degree,and the star is a nearly critical rotator with Vrot /Vc =1.00$\pm$0.2. Thisinclination is greater than the value found for \gamma Cas (about 42\degree,Stee et al. 2012), and is consistent with the inference from optical Fe IIemission profiles by Smith & Balona (2006) that the inclination should be morethan the \gamma Cas value. In the near-IR continuum, the disk of HD 110432 is 3times larger than \gamma Cas's disk. We have no direct evidence of a companionaround HD 110432, but it seems that we have a clear signature for diskinhomogeneities as detected for {\zeta} Tau. This asymmetrical disk detectionmay be interpreted within the one-armed oscillation viscous disk framework.Another finding is that the disk size in the near-IR is similar to other Bestars with different spectral types and thus may be independent of the stellarparameters, as found for classical Be stars.

Evidence of an asymmetrical Keplerian disk in the Br{\gamma} and He I emission lines around the Be star HD 110432