PHASE REFERENCED IMAGING AND MICRO-ARCSEC ASTROMETRY (PRIMA) TECHNICAL DESCRIPTION AND IMPLEMENTATION

PRIMA will be designed to make use of the Dual feed capability of the Very Large Telescope Interferometer for both Unit and Auxiliary Telescopes. With PRIMA the global limiting magnitude of the VLTI will gain about six magnitudes in H, K and N. The system is designed to perform high accuracy (10 μas) narrow angle astrometry in band H or K, aperture synthesis (phase reference imaging) and model constrained imaging in bands J, H, K and N (depending on the instrument: VINCI, AMBER, MIDI).