MagAO-2K: The 2 kHz Extreme-AO Upgrade of the Magellan AO System and H2RG Upgrade of the Clio IR Camera

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When the light from a star or other astronomical object enters the Earth's atmosphere, atmospheric turbulence can distort the light in a number of different ways. A manifestation of this atmospheric distortion is the twinkling of starlight, also known as scintillation. The scintillation of starlight is highly problematic for astronomers, as scintillation not only results in detrimental distortion of the telescope image, but also significant variations in both the position and brightness of astronomical objects. The field of Adaptive Optics (AO) attempts to measure and then correct the effects of atmospheric turbulence on astronomical observations. MagAO is an adaptive optics system that was recently deployed on one of the two Magellan telescopes at Las Campanas Observatory in Chile and has been shown to have a significant impact in removing the effects of atmospheric turbulence. Recent highlights from the MagAO commissioning run include imaging the HR 4796 A planetary debris disk at high resolution and imaging the 2M 1207 b planetary mass companion. The subject proposal will produce a significant upgrade to the current MagAO system, providing an "extreme-AO" system, which will open significantly new discovery space in numerous scientific areas. The current MagAO system operates with both visible and infrared science cameras, locking on natural guide stars (NGS) from 0th to 16th magnitude (R-band). MagAO utilizes a pyramid wavefront sensor to measure atmospheric turbulence, and includes a 585-actuator adaptive secondary mirror to provide seeing correction to the science data wavefronts prior to being recorded by the science cameras. MagAO controls up to 378 modes and operates at frame rates up to 1kHz. The subject proposal will build upon the current MagAO system to develop significant improvements. The proposal has two goals. The first goal is to upgrade the MagAO system to extreme-AO performance by 1) re-calibrating the adaptive secondary mirror position control system, 2) increasing the pyramid wavefront sensor sampling frequency from 1 kHz to 2 kHz, 3) implement advanced vibration control algorithms, and 4) upgrade the adaptive secondary mirror firmware. The second goal of the subject proposal is to upgrade the infrared science camera with a Teledyne H2RG detector. The resultant system upgrades will transform MagAO into a 2 kHz, 450 mode extreme-AO system with 4 mas rms jitter.