RAVEN, a Multi-Object Adaptive Optics technology and science demonstrator
Dave Andersen, Célia Blain, Colin Bradley, Darryl Gamroth, Meguru Ito, Kate Jackson, Olivier Lardière, Reston Nash, Shin Oya, Laurie Pham, Dave Robertson, Jean-Pierre Véran
Adaptive Optics Laboratory, Mechanical Engineering Department, University of Victoria, BC, Canada
Herzberg Institute of Astrophysics, NRC-CNRC, Victoria, BC, Canada
Subaru Telescope, Hilo, HI, USA
The University of Victoria Adaptive Optics Laboratory, the Herzberg Institute of Astrophysics and Subaru Observatory are undertaking a preliminary design study for a Multi-Object Adaptive Optics (MOAO) technology and science demonstrator called Raven. Raven will be mounted on the Subaru NIR Nasmyth platform and will feed the IRCS imager and spectrograph. The baseline design calls for three natural guide star (NGS) wavefront sensors (WFS), one on-axis laser guide star (LGS) WFS and two science pickoff arms that will patrol a 2 arcminute diameter field of regard (FOR). Sky coverage is an important consideration for a science demonstrator. End-to-end simulations of Raven show that a 10x10 subaperture adaptive optics (AO) system can meet the science requirements, i.e. 30% of the energy ensquared (EE) within a 140mas slit using three R<14 NGSs, and 40% EE with the addition of the central LGS. An overview of the Raven project is presented, including the top-level requirements, science cases, opto-mechanical design, calibration procedures and the hardware and software architecture.