Combining optical interferometry with lunar occultations

Datasets obtained from lunar occultation in the thermal infrared with a classical direct imaging system are compared to those obtained with a two telescope interferometer. Angular resolution and sensitivity achievable with ESO's VLT- Interferometer as λ≈10 μm are roughly identical to the precision with which 1-dimensional cuts can be reconstructed from lunar occultations. Prototype results obtained at a 4m class telescope with lunar occultation only are presented. The concepts of an algorithm to reconstruct interferometric data under the constrain of compatibility with a light curve derived from a lunar occultation event is given. The improvement of image reconstruction of the combined data set relative to the single data sets is demonstrated by calculating theoretical point spread functions. The estimated 'PSF' width for this technique at λ≈10 μm is of order of 0.03 inches.