Aperture synthesis image reconstruction study for the mid-infrared VLTI imager MATISSE

Aperture synthesis imaging provides a way to overcome the ambiguities which often exist in the interpretation of single-baseline interferometric visibility measurements. The mid-infrared imager MATISSE (Multi AperTure mid-Infrared SpectroScopic Experiment), which was proposed to ESO as a second-generation VLTI instrument, is designed to combine up to four 8.2 m VLTI UTs or 1.8 m ATs while simultaneously providing a high spectroscopic resolution. To demonstrate that MATISSE will allow high-quality interferometric imaging within realistic observation time constraints, we performed an image reconstruction study, for which we simulated the uv-coverage achievable in 3, 5, or 7 nights with 3 or 4 telescopes. As input image for our studies, a protostellar disk image was simulated with the radiative transfer code MC3D1 . From the simulated visibilities and closure phases, we derived aperture synthesis images using the Building Block algorithm2 . The main features of the disk image could be reconstructed in the presence of noise and assuming the sparse uv-coverage achievable within just 3 nights of observations.