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Classical Be stars are hot non-supergiant stars surrounded by a gaseouscircumstellar disk that is responsible for the observed infrared (IR) excessand emission lines. The influence of binarity on these phenomena remainscontroversial. We followed the evolution of the environment surrounding thebinary Be star $\delta$ Scorpii one year before and one year after the 2011periastron to check for any evidence of a strong interaction between itscompanion and the primary circumstellar disk. We used the VLTI/AMBERspectro-interferometric instrument operating in the K band in high (12000)spectral resolution to obtain information on both the disk geometry andkinematics. Observations were carried out in two emission lines: Br$\gamma$(2.172\,$\mu$m) and $\ion{He}{i}$ (2.056\,$\mu$m). We detected some importantchanges in $\delta$ Scorpii's circumstellar disk geometry between the firstobservation made in April 2010 and the new observation made in June 2012.During the last two years the disk has grown at a mean velocity of0.2\,km\,s$^{-1}$. This is compatible with the expansion velocity previouslyfound during the 2001-2007 period. The disk was also found to be asymmetric atboth epochs, but with a different morphology in 2010 and 2012. Considering theavailable spectroscopic data showing that the main changes in the emission-lineprofiles occurred quickly during the periastron, it is probable that thedifferences between the 2010 and 2012 disk geometry seen in our interferometricdata stem from a disk perturbation caused by the companion tidal effects.However, taking into account that no significant changes have occurred in thedisk since the end of the 2011 observing season, it is difficult to understandhow this induced inhomogeneity has been "frozen" in the disk for such a longperiod.

The binary Be star $\delta$ Scorpii at high spectral and spatial resolution : II The circumstellar disk evolution after the periastron