论文标题
针对外旋转的高对比度成像的第四阶冠型，并分段望远镜
Fourth-order Coronagraph for High-Contrast Imaging of Exoplanets with Off-axis Segmented Telescopes
论文作者
论文摘要
我们提出了一个带有四阶空的可加冕系统，用于分割离轴的望远镜，该系统对望远镜指向误差的望远镜和有限的角直径非常不敏感，以实现对潜在可居住行星的高对比度成像。冠状系统的内部工作角度接近$1λ/d $，并且没有外部限制。提出的冠状动脉膜系统由新的焦平面掩模和二阶空的优化lyot停止组成。新的焦平面掩模是带有相位调制的带限制面罩的扩展。我们通过将两个新的冠状系统连续地构造出具有四阶空的冠状系统，以相互正交。提出的系统仅限于窄带使用情况。提出的冠状动脉系统的特征是通过分析得出的，其中包括：（1）由于有限的恒星直径和望远镜的抖动引起的恒星灯泄漏，以及（2）峰值吞吐量。我们根据这些分析表达式实现了该冠状动脉粥样硬化系统的性能模拟，考虑到单色光为0.75 $ \MATHRMμ$ m，并且直径为850万的单轴均为主镜。得益于面具的宽大工作区域，结果表明，在望远镜指向抖动小于$0.01λ/d \ yout 240 $ as的条件下，可以检测到绕着K和G码头的陆地行星。拟议的冠状动脉系统有望检测潜在的可居住的行星，并具有未来空间的远轴六角形分割的望远镜。
We propose a coronagraphic system with fourth-order null for off-axis segmented telescopes, which is sufficiently insensitive to the telescope pointing errors and finite angular diameter of the host star to enable high-contrast imaging of potentially habitable planets. The inner working angle of the coronagraphic system is close to $1λ/D$, and there is no outer limit. The proposed coronagraphic system is made up of a new focal plane mask and an optimized Lyot stop with the second-order null. The new focal plane mask is an extension of the band-limited masks with a phase modulation. We construct a coronagraphic system with fourth-order null by placing two of the new coronagraph systems in succession to be orthogonal to each other. The proposed system is limited to narrow-band usage. The characteristics of the proposed coronagraph system are derived analytically, which includes: (1)the leak of stellar lights due to finite stellar diameter and pointing jitter of a telescope, and (2)the peak throughput. We achieve the performance simulations of this coronagraphic system based on these analytical expressions, considering a monochromatic light of 0.75$\mathrmμ$m and off-axis primary mirror with a diameter of 8.5m. Thanks to the wide working area of the mask, the result shows that terrestrial planets orbiting K and G-dwarfs can be detected under the condition that the telescope pointing jitter is less than $0.01λ/D\approx240$as. The proposed coronagraphic system is promising for detection of potentially habitable planets with future space off-axis hexagonally segmented telescopes.
