发表机构
The Open University; Imperial College London; Max Planck Institute for Astronomy (MPIA); Cornell University（开放大学; 帝国理工学院; 马克斯·普朗克天文学研究所; 康奈尔大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
针对恒星污染影响系外行星透射光谱的问题，提出结合JWST和哈勃望远镜的观测策略，通过合成反演证明紫外-光学波段可有效约束黑子和谱斑参数，打破与行星参数的简并。
AI 中文摘要
系外行星的透射光谱为研究其大气成分、结构和动力学提供了重要窗口，尤其是在詹姆斯·韦布空间望远镜（JWST）时代。随着观测数据质量的提高以及由此带来的约束精度的提升，我们越来越敏感于模型和观测中的系统性偏差来源。其中一个重要例子是凌星光源效应，即恒星光球中的不均匀特征（黑子和谱斑）会在系外行星透射光谱上留下额外的光谱特征。为了准确恢复行星的大气性质，必须考虑或消除这种恒星污染的影响。在光谱反演分析中纳入参数化的黑子和谱斑模型，正日益成为解决这一问题的方案，但其准确性受限于恒星光谱模型的精度。在本文中，我们提出了一种观测策略，结合JWST和哈勃空间望远镜的同步数据，以进一步约束这些模型。我们进行了合成反演，以演示如何约束星斑和谱斑参数；我们测试了在反演中使用不同模型光谱的影响；并考虑了变星活动对相干叠加凌星数据以达到所需信噪比的影响。我们发现，紫外和光学波长对于打破恒星污染与行星参数之间的简并至关重要。
英文摘要
Transmission spectroscopy of exoplanets provides an important window into their atmospheric composition, structure and dynamics, especially in the JWST era. As the quality of the observational data and therefore the precision of our constraints improves, we become increasingly sensitive to sources of systematic bias in our models and observations. One significant example of this is the Transit Light Source Effect, in which heterogeneous features in the stellar photosphere - spots and faculae - imprint additional spectral signatures onto exoplanet transmission spectra. The effects of this stellar contamination must be accounted for or removed in order to accurately recover the planet's atmospheric properties. Including parameterized models of spots and faculae within spectral retrieval analysis is increasingly adopted as a solution to this problem, but is limited by the accuracy of models of stellar spectra. In this paper, we outline an observational strategy combining simultaneous data from JWST and the Hubble Space Telescope that would enable us to further constrain these models. We perform synthetic retrievals to demonstrate how we could constrain starspot and faculae parameters; we test the impact of using different model spectra in the retrieval; and we consider the impact of variable stellar activity on coadding transits to achieve the desired signal-to-noise. We find that ultraviolet and optical wavelengths are key for breaking degeneracies between stellar contamination and planetary parameters.
Comments11 pages, 7 figures, submitted to RASTI. Corrected error in figure 4 from v1
