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arXiv · 1407.2278

On-sky performance during verification and commissioning of the Gemini Planet Imager's adaptive optics system

Lisa A. Poyneer·Robert J. De Rosa·Bruce Macintosh·David W. Palmer·Marshall D. Perrin·Naru Sadakuni·Dmitry Savransky·Brian Bauman·Andrew Cardwell·Jeffrey K. Chilcote·Daren Dillon·Donald Gavel·Stephen J. Goodsell·Markus Hartung·Pascale Hibon·Fredrik T. Rantakyro·Sandrine Thomas·Jean-Pierre Veran
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Abstract

The Gemini Planet Imager instrument's adaptive optics (AO) subsystem was designed specifically to facilitate high-contrast imaging. It features several new technologies, including computationally efficient wavefront reconstruction with the Fourier transform, modal gain optimization every 8 seconds, and the spatially filtered wavefront sensor. It also uses a Linear-Quadratic-Gaussian (LQG) controller (aka Kalman filter) for both pointing and focus. We present on-sky performance results from verification and commissioning runs from December 2013 through May 2014. The efficient reconstruction and modal gain optimization are working as designed. The LQG controllers effectively notch out vibrations. The spatial filter can remove aliases, but we typically use it oversized by about 60% due to stability problems.

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Lisa A. Poyneer, Robert J. De Rosa, Bruce Macintosh, David W. Palmer, Marshall D. Perrin, Naru Sadakuni, Dmitry Savransky, Brian Bauman, Andrew Cardwell, Jeffrey K. Chilcote, Daren Dillon, Donald Gavel, Stephen J. Goodsell, Markus Hartung, Pascale Hibon, Fredrik T. Rantakyro, Sandrine Thomas, Jean-Pierre Veran. 2014-07-08. On-sky performance during verification and commissioning of the Gemini Planet Imager's adaptive optics system. https://doi.org/10.1117/12.2057092

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