NEXT：荷兰系外行星测试平台I. 目标与光机设计
NEXT: The Netherlands EXoplanet Testbed I. Goals and opto-mechanical design
AI总结：
荷兰系外行星测试平台NEXT为满足下一代ELTs和未来空间天文台需求，开发验证XAO与日冕仪技术，完成光机设计及性能模拟，目标800nm、5λ/D处原始对比度10⁻⁷（终目标10⁻⁸）。
AI中文摘要：
我们报道荷兰系外行星测试平台（Netherlands EXoplanet Testbed，NEXT）的目标、设计及正在进行的开发工作，该平台是莱顿大学正在建造的高对比度成像测试平台。NEXT旨在开发和验证极端自适应光学（extreme adaptive optics，XAO）及日冕仪技术与算法，以达到下一代极大望远镜（Extremely Large Telescopes，ELTs）和未来空间天文台的高对比度成像仪所需的性能水平。其公共路径中的所有动力光学元件均为定制离轴抛物面镜，使该平台在到达科学相机前完全为反射式，工作波段为可见光至近红外（500-1800 nm）。它结合了采用ALPAO低音镜和Boston Micromachines千单元变形镜（kilo-DM）作为高音镜的低音-高音XAO模块，以及支持常见日冕仪架构和用于暗区挖掘的焦平面波前控制的日冕仪臂，并为一套波前传感器预留了空间。该设计的目标是在800 nm、5λ/D处达到原始对比度10⁻⁷，最终目标为10⁻⁸。我们介绍了该测试平台的光机设计、为达到这些对比度水平所做的关键权衡，以及对其预测性能的菲涅耳传播模拟。
英文摘要：
We report on the goals, design, and ongoing development of the Netherlands EXoplanet Testbed (NEXT), a high-contrast imaging testbed under construction in Leiden. NEXT is designed to develop and validate technologies and algorithms for extreme adaptive optics (XAO) and coronagraphy at the performance levels required by the next generation of high-contrast imagers on the Extremely Large Telescopes (ELTs) and future space observatories. All powered optics in the common path are custom off-axis parabolas, making the bench fully reflective up to the science cameras, and it operates from the visible to the near-infrared (500-1800 nm). It combines a woofer-tweeter XAO module, using an ALPAO woofer and a Boston Micromachines kilo-DM as tweeter, with a coronagraphic arm that supports common coronagraph architectures and focal-plane wavefront control for dark-hole digging, and reserves space for a suite of wavefront sensors. The design targets a raw contrast of $10^{-7}$ (goal: $10^{-8}$) at $5λ/D$ and 800 nm. We present the opto-mechanical design of the testbed, the key trade-offs made to reach these contrast levels, and Fresnel-propagation simulations of its predicted performance.
