ShaneAO: wide science spectrum adaptive optics system for the Lick Observatory

Donald Gavel; Renate Kupke; Daren Dillon; Andrew Norton; Chris Ratliff; Jerry Cabak; Andrew Phillips; Connie Rockosi; Rosalie McGurk; Srikar Srinath; Michael Peck; William Deich; Kyle Lanclos; John Gates; Michael Saylor; Jim Ward; Terry Pfister

doi:10.1117/12.2055256

arXiv · 1407.8207

ShaneAO: wide science spectrum adaptive optics system for the Lick Observatory

Donald Gavel·Renate Kupke·Daren Dillon·Andrew Norton·Chris Ratliff·Jerry Cabak·Andrew Phillips·Connie Rockosi·Rosalie McGurk·Srikar Srinath·Michael Peck·William Deich·Kyle Lanclos·John Gates·Michael Saylor·Jim Ward·Terry Pfister

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Abstract

A new high-order adaptive optics system is now being commissioned at the Lick Observatory Shane 3-meter telescope in California. This system uses a high return efficiency sodium beacon and a combination of low and high-order deformable mirrors to achieve diffraction-limited imaging over a wide spectrum of infrared science wavelengths covering 0.8 to 2.2 microns. We present the design performance goals and the first on-sky test results. We discuss several innovations that make this system a pathfinder for next generation AO systems. These include a unique woofer-tweeter control that provides full dynamic range correction from tip/tilt to 16 cycles, variable pupil sampling wavefront sensor, new enhanced silver coatings developed at UC Observatories that improve science and LGS throughput, and tight mechanical rigidity that enables a multi-hour diffraction- limited exposure in LGS mode for faint object spectroscopy science.

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Donald Gavel, Renate Kupke, Daren Dillon, Andrew Norton, Chris Ratliff, Jerry Cabak, Andrew Phillips, Connie Rockosi, Rosalie McGurk, Srikar Srinath, Michael Peck, William Deich, Kyle Lanclos, John Gates, Michael Saylor, Jim Ward, Terry Pfister. 2014-07-30. ShaneAO: wide science spectrum adaptive optics system for the Lick Observatory. https://doi.org/10.1117/12.2055256

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