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

当来自星星或其他天体的光线进入地球大气层时，大气湍流会以多种不同的方式扭曲光线。这种大气扭曲的一个表现是星光的闪烁，也被称为闪烁。星光的闪烁对天文学家来说是一个很大的问题，因为闪烁不仅会导致望远镜图像的有害失真，还会导致天文物体的位置和亮度发生显着变化。自适应光学（AO）领域试图测量并校正大气湍流对天文观测的影响。MagAO是一个自适应光学系统，最近被安装在智利Las Campanas天文台的两台麦哲伦望远镜之一上，并已被证明在消除大气湍流影响方面具有重大影响。MagAO调试运行的最新亮点包括以高分辨率对HR 4796 A行星碎片盘进行成像，以及对2M 1207 B行星质量伴星进行成像。该主题提案将对当前的MagAO系统进行重大升级，提供一个“极端AO”系统，这将在许多科学领域开辟新的发现空间。目前的MagAO系统使用可见光和红外科学相机，锁定0至16等（R波段）的自然导航星（NGS）。MagAO利用金字塔波前传感器来测量大气湍流，并包括585致动器自适应次镜，以在科学相机记录之前对科学数据波前进行视宁校正。MagAO控制多达378种模式，并以高达1kHz的帧速率运行。本提案将在当前MagAO系统的基础上进行重大改进。该提案有两个目标。第一个目标是通过1）重新校准自适应次镜位置控制系统，2）将金字塔波前传感器采样频率从1 kHz增加到2 kHz，3）实施高级振动控制算法，以及4）升级自适应次镜固件，将MagAO系统升级到极端AO性能。该主题提案的第二个目标是使用Teledyne H2RG探测器升级红外科学相机。由此产生的系统升级将把MagAO转换为2 kHz、450模式的极端AO系统，具有4 mas rms抖动。

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.