标题： 基于网格的大气反演用于系外行星反射光谱的PSGnest系统 显示英文标题

标题： Grid-Based Atmospheric Retrievals for Reflected-Light Spectra of Exoplanets using PSGnest

摘要： 通过直接观测系外行星的反射光来获取其大气特性的技术，常常由于前向模型计算所带来的计算限制而受到范围上的制约。 我们开发了一组新技术，这些技术显著减少了执行检索所需的时间，同时保持了准确的结果。 我们构建了一个包含140万条预先计算的几何反照率光谱的网格，这些光谱对应于离散的参数点集。 该网格中的光谱被用来生成用于快速高效的嵌套采样例行程序PSGnest的模型。 除了初始构建光谱网格的时间外，使用PSGnest完成整个检索的时间通常只需几秒到几分钟，使用个人电脑即可。 对从网格中插值中间光谱所引起的误差进行了广泛的评估，结果显示这种偏差与其他检索误差源相比可以忽略不计，插值光谱与真实光谱之间的决定系数平均值为0.998。 我们将这些新的检索技术应用于帮助确定LuvEx型任务中用于检索各种大气和总体参数的最佳波段中心，该任务将观测几种行星原型。 我们表明，使用以0.73微米为中心的20%带宽进行的光谱观测可以与我们的新技术结合使用，无需增加观测时间，即可检测到$H_2O$和$O_2$，达到信噪比为10的要求。 这里介绍的方法将使未来天文台表征系外行星的能力得到稳健的研究。 显示英文摘要

摘要： Techniques to retrieve the atmospheric properties of exoplanets via direct observation of their reflected light have often been limited in scope due to computational constraints imposed by the forward-model calculations. We have developed a new set of techniques which significantly decreases the time required to perform a retrieval while maintaining accurate results. We constructed a grid of 1.4 million pre-computed geometric albedo spectra valued at discrete sets of parameter points. Spectra from this grid are used to produce models for a fast and efficient nested sampling routine called PSGnest. Beyond the upfront time to construct a spectral grid, the amount of time to complete a full retrieval using PSGnest is on the order of seconds to minutes using a personal computer. An extensive evaluation of the error induced from interpolating intermediate spectra from the grid indicates that this bias is insignificant compared to other retrieval error sources, with an average coefficient of determination between interpolated and true spectra of 0.998. We apply these new retrieval techniques to help constrain the optimal bandpass centers for retrieving various atmospheric and bulk parameters from a LuvEx-type mission observing several planetary archetypes. We show that spectral observations made using a 20\% bandpass centered at 0.73 microns can be used alongside our new techniques to make detections of $H_2O$ and $O_2$ without the need to increase observing time beyond what is necessary for a signal-to-noise ratio of 10. The methods introduced here will enable robust studies of the capabilities of future observatories to characterize exoplanets.