Integration of the mid-high wavefront sensor to the LINC-NIRVANA post-focal relay

LINC-NIRVANA is an infrared camera working in Fizeau interferometric mode. The beams coming from the two primary mirrors of the LBT are corrected for the effects of the atmospheric turbulence by two Multi-Conjugate Adaptive Optics (MCAO) systems, working in a scientific field of view of 2 arcminutes. One single arm MCAO system includes two wave-front sensors, driving two deformable mirrors, one for the ground layer correction (LBT secondary mirror) and one for the correction of a mid-high layer (up to a maximum distance of 15 km). The first of the two Mid-High Wavefront Sensors (MHWS) was integrated and tested as a stand-alone unit in the laboratory at INAF-Osservatorio Astronomico di Bologna, where the telescope was simulated by means of a simple afocal system illuminated by a set of optical fibers. Then the module was delivered to the MPIA laboratories in Heidelberg, where is going to be integrated and aligned to the post-focal optical relay of one LINC-NIRVANA arm, including the deformable mirror. A number of tests are in progress at the moment of this writing, in order to characterize and optimize the system functionalities and performance. A report is presented about the status of this work.