标题： 新的直接探测方法在估计系外行星发现中的完备性 显示英文标题

标题： New Completeness Methods for Estimating Exoplanet Discoveries by Direct Detection

摘要： 我们报告了新的方法，用于评估通过直接成像搜索恒星的现实观测计划，其中观测是从优化的恒星列表中选择的，并且恒星可以被多次观测。 我们展示了这些方法如何为任务及其仪器的设计提供关键见解。 这些方法提供了观测计划结果的估计：发现的概率分布（检测和/或表征），以及行星出现率（eta）的估计。 我们表明，这些参数可以从一次任务模拟中准确估计，而无需进行完整的蒙特卡洛任务模拟，并且我们证明了这种新方法的准确性。 我们的方法提供了定义特定科学目标任务的工具，例如由预期发现数量及其置信度定义的任务。 我们详细说明了如何构建优化的恒星列表以及如何选择后续观测。 我们的方法还提供了其他关键的任务属性，例如预计要搜索的恒星数量，以及零发现的概率。 由于这些属性强烈依赖于任务规模，我们的方法可直接应用于此类未来任务的设计，并根据科学性能为任务和仪器设计提供指导。 我们通过实际计算和JWST使用远距离星遮罩以减少焦平面上的散射和衍射星光的探索性设计参考任务来说明我们的新方法。 我们估计，在假设JWST观测时间的一小部分（7%）、eta=0.3和70次观测访问（受星遮罩燃料限制）的情况下，将有5颗适居的地球质量行星被发现并进行光谱分析，零发现的概率为0.004。 显示英文摘要

摘要： We report new methods for evaluating realistic observing programs that search stars for planets by direct imaging, where observations are selected from an optimized star list, and where stars can be observed multiple times. We show how these methods bring critical insight into the design of the mission & its instruments. These methods provide an estimate of the outcome of the observing program: the probability distribution of discoveries (detection and/or characterization), & an estimate of the occurrence rate of planets (eta). We show that these parameters can be accurately estimated from a single mission simulation, without the need for a complete Monte Carlo mission simulation, & we prove the accuracy of this new approach. Our methods provide the tools to define a mission for a particular science goal, for example defined by the expected number of discoveries and its confidence level. We detail how an optimized star list can be built & how successive observations can be selected. Our approach also provides other critical mission attributes, such as the number of stars expected to be searched, & the probability of zero discoveries. Because these attributes depend strongly on the mission scale, our methods are directly applicable to the design of such future missions & provide guidance to the mission & instrument design based on scientific performance. We illustrate our new methods with practical calculations & exploratory design reference missions for JWST operating with a distant starshade to reduce scattered and diffracted starlight on the focal plane. We estimate that 5 habitable Earth-mass planets would be discovered & characterized with spectroscopy, with a probability of 0 discoveries of 0.004, assuming a small fraction of JWST observing time (7%), eta=0.3, and 70 observing visits, limited by starshade fuel.