High spatial resolution study of the inner environment around two young   planetary nebulae
  We present observations of the dusty emission from the young planetary nebulae Hen2-113 and CPD-56 obtained with VLT/NACO, VLTI/MIDI. The central stars of these two objects are Wolf-Rayet stars of the same spectral type [WC10]. They share an impressive number of characteristics and are located at similar distance, making the detection of any differences in their close environment of great interest. Hen2-113 exhibits a clear ring-like structure of about 0.4 arcsec in diameter, superimposed to a more diffuse environment visible in L', M' and 8.7 micron bands. No clear core could be detected for this object with MIDI through the N band. The dusty environment of CPD-568032 is much more compact, dominated by a bright, barely resolved, core whereas the visible nebula exhibits an amazing complexity. From MIDI 8.7 micron acquisition images (dominated by PAHs emission), the extension and geometry of the core have been estimated and compared to the STIS/HST observations (De Marco et al., 1997 and 2002). Moreover, high SNR fringes at low level have been detected with projected baselines between 40 and 45 meters. This clear signal is interpreted in terms of the bright inner rim of a dusty disk exposed to the flux from the Wolf-Rayet star. The geometrical parameters of the N band flux distribution are well constrained by means of simple geometrical models and a simple radiative transfer model has been developed to extract the physical parameters of the disk. 
Olivier Chesneau (LG)