With the advent of 30- to 40-m class ground-based telescopes in the mid-2020s, direct imaging of exoplanets is bound to take a new major leap. Among the approved projects, the Mid-infrared Extremely Large Telescope (ELT) Imager and Spectrograph (METIS) instrument for the ELT holds a prominent spot; by observing in the mid-infrared regime, it will be perfectly suited to study a variety of exoplanets and protoplanetary disks around nearby stars. Equipped with two of the most advanced coronagraphs, the vortex coronagraph and the apodizing phase plate, METIS will provide high-contrast imaging (HCI) in L-, M- and N-bands, and a combination of high-resolution spectroscopy and HCI in L- and M-bands. We present the expected HCI performance of the METIS instrument, considering realistic adaptive optics residuals, and investigate the effect of the main instrumental errors. The most important sources of degradation are identified and realistic sensitivity limits in terms of planet/star contrast are derived.

中文翻译：

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METIS高对比度成像：设计和预期性能

随着2020年代中期30至40 m级地基望远镜的问世，系外行星的直接成像必将迈出新的重大飞跃。在已批准的项目中，用于ELT的中红外超大型望远镜（ELT）成像仪和光谱仪（METIS）仪器占据突出位置；通过观察中红外区域，它将非常适合研究附近恒星周围的各种系外行星和原行星盘。METIS配备了两个最先进的日冕仪，即旋涡日冕仪和变迹相板，将提供L，M和N波段的高对比度成像（HCI），以及高分辨率光谱学和HCI的组合L和M波段。考虑到实际的自适应光学残差，我们提出了METIS仪器的预期HCI性能，并调查主要仪器误差的影响。确定了最重要的退化源，并得出了有关行星/恒星对比度的实际灵敏度极限。