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We present diffraction-limited bispectrum speckle interferometry observationsof four well-known Herbig Ae/Be (HAeBe) stars, LkHa 198, Elias 1, HK Ori andV380 Ori. For two of these, LkHa 198 and Elias 1, we present the firstunambiguous detection of close companions. The plane of the orbit of the newLkHa 198 companion appears to be significantly inclined to the plane of thecircumprimary disk, as inferred from the orientation of the outflow. We showthat the Elias 1 companion may be a convective star, and suggest that it couldtherefore be the true origin of the X-ray emission from this object. In thecases of HK Ori and V380 Ori, we present new measurements of the relativepositions of already-known companions, indicating orbital motion. For HK Ori,photometric measurements of the brightness of the individual components in fourbands allowed us to decompose the system spectral energy distribution (SED)into the two separate component SEDs. The primary exhibits a strong infraredexcess which suggests the presence of circumstellar material, whereas thecompanion can be modelled as a naked photosphere. The infrared excess of HK OriA was found to contribute around two thirds of the total emission from thiscomponent, suggesting that accretion power contributes significantly to theflux. Submillimetre constraints mean that the circumstellar disk cannot beparticularly massive, whilst the near-infrared data indicates a high accretionrate. Either the disk lifetime is very short, or the disk must be seen in anoutburst phase.Comment: 14 pages, 10 figures, 22 separate figure file

Close binary companions of the HAeBe stars LkHα198, Elias 1, HK Ori and V380 Ori