Toward the Interferometric First Light of LBT: LINC-NIRVANA

Multi Conjugate Adaptive Optics (MCAO) allows one to obtain images close to the diffraction limit of a telescope on relatively large fields, at least when compared with the few arc–seconds of single star Adaptive Optics. This feature is fundamental to push to the limit the performance of the new generation of astronomical instruments, and this is why several 8–m class telescopes are designing and building MCAO systems. We are finishing the integration of one of the two MCAO wavefront sensor of MAD, a demonstrator that will be installed toward the end of the year at the Very Large Telescope (VLT). At the same time we are designing an instrument for the Large Binocular Telescope (LBT) based on the Layer–Oriented MCAO Technique, namely LINC-NIRVANA. Our contribution to this project, the first light of which is foreseen at the end of 2006, concerns the construction of four wavefront sensors for the double MCAO system (one for each telescope), with the aim of removing the atmospheric disturbance from the two beams which are going to be used in a Fizeau interferometric way. The status of these projects will be presented.