Compact designs for high-resolution astronomical spectrometers

用于详细研究系外行星的天文光谱仪需要宽带、高效率、高分辨率和极高的机械稳定性。这些设计约束可以通过“梯级”光谱仪的设计来满足，该设计由一个高色散光栅和一个分离衍射级的棱镜组成。这些仪器已经存在，但它们体积庞大（汽车大小）且难以维护（大型真空/温度控制外壳，约3 m^3体积）。在这个项目中，学生将设计几十厘米大小的紧凑型光谱仪，然后使用光纤和基本的自适应光学系统将其耦合到望远镜上。该项目将包括设备的光学设计，优化光学以最小化像差，执行机械设计，并使用新型材料（碳纤维复合材料）最小化热膨胀的影响，并通过天空测量展示仪器的性能。

Astronomical spectrometers for detailed exoplanet studies need to be broad band, highly efficient, high resolution and extremely mechanically stable. These design constraints can be satisfied with an 'echelle' spectrometer design which consists on a high dispersion grating combined with a prism to separate the diffraction orders. These instruments already exist but they are bulky (size of a car) and difficult to maintain (large vacuum/tempeature controled enclosures, ~3 m^3 volumes). In this project the student will design compact spectrometers of a few tens of cm is size which then will be coupled to telescopes using optical fibres and basic adaptive optics systems. The project will consist on optical designing the device, optimize the optics to minimize aberrations, perform its mechanical design and minimize effects of thermal expansion using novel materials (carbon fibre composites) and demonstrate the performance of the instrument using on-sky measurements.