Stellar Atmospheres in the era of Big Data

在未来的十年里，天文学调查将监测银河系内外数十亿颗恒星的光谱。从这些光谱中，天文学家将描绘恒星的特性，包括它们的表面温度、引力和原子组成，以探测银河系的形成和演化历史；宇宙中元素的演化和创造；以及恒星的结构和演化。但是，这些大型调查依赖于我们对恒星大气的理解以及支撑这些模型的物理原理。以同样的方式，我们使用模型恒星大气来探测和表征高角分辨率的系外行星过境和对恒星盘强度敏感的恒星的光学干涉观测。在接下来的十年里，大型光谱调查，如大型综合测量望远镜（LSST）、莫纳克亚光谱探测器（MSE）和SpecTel，与光学干涉测量设备和行星过境任务（如凌日系外行星测量卫星（TESS））的结合，将为恒星大气的精确物理提供新的联合测试。这种方法是一种新颖的方法，可以连接两种恒星大气物理测试，并以前所未有的细节了解恒星。两种方法的观测结果，光谱和高角度分辨率，都依赖于恒星大气模型来物理和精确地解释它们。目前还没有开源的建模程序套件可以高精度地探测观测结果。我将利用即将进行的大量测量，通过使用最先进的恒星大气代码卫星，为拟合来自巡天的恒星光谱、拟合行星凌日和光学干涉测量创建一个开源环境。这使我们能够测量基本的恒星参数，如质量、半径和温度以及组成；通过凌日测量作为波长的函数更精确地表征系外行星大气；测量银河系中恒星的化学历史；在局部尺度上探索宇宙。这些进步将允许对恒星大气进行动态和自动化建模，以构建跨越众多参数的网格，如恒星表面温度、质量和半径，以及每种元素的丰度，同时测试恒星大气中的附加物理，如恒星对流、旋转、化学分层。加拿大的天文学界在构建大型光谱调查（如LSST和MSE）以及通过MOST卫星任务和即将到来的CASTOR和JWST任务进行的行星过境观测方面发挥了领导作用。这项工作旨在创造计算资源，以获得对银河考古学的新见解，并表征恒星表面和系外行星大气。

In the coming decade astronomy surveys will monitor the spectra from billions of stars in our Galaxy and beyond. From these spectra, astronomers will characterize the properties of stars, including their surface temperatures, gravities and atomic composition to probe the formation and evolution history of the Galaxy; the evolution and creation of elements in our Universe; and the structure and evolution of stars. But, these big surveys rely on our understanding stellar atmospheres and the physics anchoring those models. In the same way, we employ model stellar atmospheres to probe and characterize high-angular resolution exoplanetary transits and optical interferometric observations of stars that are sensitive to the intensity across the stellar disk. The combination of of big spectral surveys in the next decade, such as the Large Synoptic Survey Telescope (LSST), the Maunakea Spectroscopic Explorer (MSE), and SpecTel, with optical interferometric facilities and with planetary transit missions such as Transiting Exoplanet Survey Satellite (TESS)  will offer novel joint tests of the precise physics of stellar atmospheres. This approach is a novel methodology to bridge two tests of the physics of stellar atmospheres and lead about stars in unprecedented detail. The observations from both methods, spectroscopic and high-angular resolution, rely on models of stellar atmospheres to physically and precisely interpret them. There are currently no open source suites of modelling programs that can probe observations with the high precision. I will take advantage of the abundance of forthcoming measurements by using the state-of-the-art stellar atmospheres code SAtlas to create an open source environment for both fitting stellar spectra from surveys and fitting planet transit and optical interferometric measurements. This allows us to measure fundamental stellar parameters such as mass, radius and temperature along with composition; to more precisely characterize exoplanet atmospheres via transit measurements as function of wavelength; to measure the chemical history of stars across our Galaxy; and probe the cosmology at the local scale. These advancements will allow for dynamic and automated modelling of stellar atmospheres to construct grids across numerous parameters such as stellar surface temperature, mass and radius, and abundance of each element, along with testing additional physics in stellar atmospheres such as stellar convection, rotation, chemical stratification. The astronomy community in Canada has demonstrated leadership in constructing large spectral surveys such as LSST and MSE along with planetary transit observations through the MOST satellite missions and upcoming CASTOR and JWST missions. This work aims to create computational resources for gaining new insights into Galactic Archaeology and for characterizing stellar surfaces and exoplanetary atmospheres.