LLAMAS: A Facility Integral Field Spectrograph for the Magellan Telescopes

积分场光谱(IFS)是一种通过光学操作天文望远镜收集的光来构建宇宙3D图像的技术，类似于CAT扫描或其他3D医学渲染。利用微透镜和光纤光学光刻技术的进步，人们可以根据进入望远镜的每条光线在天空中的位置和颜色--物理上映射到星系的速度(通过多普勒频移)或与地球的距离--来对每条光线进行分类。IF仪器的成本是由收集的大量数据推动的，因为它们的信息率大约是传统光谱仪的一百倍。大透镜阵列麦哲伦光谱仪(LLAAS)使用商品化的数字CCD相机来应对这一挑战，在直径6.5米的麦哲伦望远镜上对宽视场进行光谱成像。大羊驼将通过一项开放获取协议向美国天文学社区提供，并将推动对爆炸性天体物理瞬变以及星系形成和聚集的研究。除了建造大羊驼，麻省理工学院的仪器团队还与马萨诸塞州萨默维尔公立高中的FabLab Maker空间合作。他们将共同教授一门望远镜制造课程，让参与者接触到对未来工程经济至关重要的基于团队的设计、光学和CAD/附加制造方法。LLAMAS设计用于(1)大型天文观测望远镜(LSST)发现的天体物理瞬变的快速有效光谱，(2)由Sunyaev-Zel？dovich对南方天空的测量确定的星系团的单点红移和动力学测量，以及(3)对遥远星系的周星系晕内Lymanα和富金属气体流动的单点发射和吸收测量。它将使用2400根光纤以0.75英寸的空间分辨率产生37“x 37”视场的光谱图像(可扩展到60“x 60”)。每根光纤在一次曝光中产生覆盖整个光学带通(350-980 nm)的R=2200的光谱。大羊驼将是美国大型望远镜上第一个可以看到的有限的、弧线级的IF。作为一种永久性设施工具，它将通过麦哲伦三人组的轮换，每年365个晚上可用。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Integral field spectroscopy (IFS) is a technique to construct 3D images of the universe analogous to CAT scans or other 3D medical renderings, by optically manipulating the light collected by astronomical telescopes. Using advances in lithographic manufacture of microscopic lenses and fiberoptics, one can sort each light ray entering a telescope according to its position on the sky, and its color -- which physically maps onto a galaxy's velocity (via the Doppler shift) or distance from Earth. The cost of IFS instruments is driven by the large volume of collected data, since their information rate exceeds that of a conventional spectrometer by roughly a hundred-fold. The Large Lenslet Array Magellan Spectrograph (LLAMAS) uses commoditized digital CCD cameras to address this challenge, spectrally imaging a wide field-of-view on the 6.5-meter diameter Magellan Telescopes. LLAMAS will be available to the US astronomical community through an open-access agreement, and will advance studies of explosive astrophysical transients, and the formation and clustering of galaxies. In addition to building LLAMAS, the MIT-based instrument team is partnering with the FabLab maker space of the Somerville, MA Public High School. They will co-teach a telescope-making course that exposes participants to team-based design, optics, and CAD/additive manufacturing methods central to the future engineering economy.LLAMAS is designed for (1) rapid and efficient spectroscopy of astrophysical transients discovered by the Large Synoptic Survey Telescope (LSST), (2) single-pointing redshift and dynamical measurements of galaxy clusters identified by Sunyaev-Zel?dovich surveys of the Southern sky, and (3) single-pointing emission and absorption measurements of Lyman alpha and metal-enriched gas flows within the circumgalactic halos of distant galaxies. It will produce spectral images of a 37" x 37" field of view (scalable to 60" x 60") at 0.75" spatial resolution using 2400 optical fibers. Each fiber produces a spectrum of R=2200 covering the full optical bandpass (350-980 nm) in a single exposure. LLAMAS will be the first seeing-limited, arcminute-class IFS available on a large US telescope. As a permanent facility instrument, it will be available 365 nights per year via rotation of the Magellan tertiary.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.