论文标题
使用带有ARCIS的相曲线数据在3D中取回外球星氛围：将WASP-43B应用于
Exoplanet atmosphere retrievals in 3D using phase curve data with ARCiS: application to WASP-43b
论文作者
论文摘要
目标。为了创建一个封装外部大气的3D性质的检索框架，并将其应用于观察到的发射相曲线和热木星系外球星WASP-43B的发射相曲线和透射光谱。方法。我们介绍了3D框架，该框架可以作为GitHub的独立模块免费提供。我们使用大气建模和贝叶斯检索套件Arcis（系外行星科学的巧妙建模代码）在同时传播（HST/WFC3）上进行8 3D检索（HST/WFC3）和相位依赖性发射（HST/WFC3，Spitzer/spitzer/irac），对WASP-43B作为一个案例研究。我们评估输入假设如何影响我们的检索结果。特别是，我们考虑限制平衡化学与自由分子检索，无云与参数云的情况，以及使用已从两种不同文献来源降低的Spitzer相位数据。对于自由化学检索，我们取回了H2O，CH4，CO，CO2，ALO和NH3作为相的函数的丰度，并且考虑了更多的物种用于平衡化学检索。结果。我们发现对于所有假定平衡化学的检索设置，我们发现一致的超极性C/O（0.6-0.9）和超极金属度（1.7-2.9 DEX）。大气热分布，热点偏移（不同的Spitzer数据集比4.5）和温度结构受Spitzer发射相数据的影响。比较与WASP-43B的其他研究进行了比较，包括可用的GCM模拟。结论。我们开发的参数化3D设置提供了一个有价值的工具，可以分析广泛的观察数据集，例如光谱相曲线。与James Webb太空望远镜（JWST）和Ariel这样的任务进行的近乎想象的观察将大大提高我们对WASP-43B等系外行星气氛的理解。
Aims. To create a retrieval framework which encapsulates the 3D nature of exoplanet atmospheres, and to apply it to observed emission phase curve and transmission spectra of hot Jupiter exoplanet WASP-43b. Methods. We present our 3D framework, which is freely available as a stand-alone module from GitHub. We use the atmospheric modelling and Bayesian retrieval package ARCiS (ARtful modelling Code for exoplanet Science) to perform 8 3D retrievals on simultaneous transmission (HST/WFC3) and phase-dependent emission (HST/WFC3, Spitzer/IRAC) observations of WASP-43b as a case study. We assess how input assumptions affect our retrieval outcomes. In particular we look at constraining equilibrium chemistry vs a free molecular retrieval, the case of no clouds vs parametrised clouds, and using Spitzer phase data that have been reduced from two different literature sources. For the free chemistry retrievals, we retrieve abundances of H2O, CH4, CO, CO2, AlO, and NH3 as a function of phase, with many more species considered for the equilibrium chemistry retrievals. Results. We find consistent super-solar C/O (0.6-0.9) and super-solar metallicities (1.7-2.9 dex) for all retrieval setups that assume equilibrium chemistry. Atmospheric heat distribution, hotspot shift (15.6 vs 4.5 for different Spitzer datasets), and temperature structure are influenced by the Spitzer emission phase data. Comparisons are made with other studies of WASP-43b, including available GCM simulations. Conclusions. The parametrised 3D setup we have developed provides a valuable tool to analyse extensive observational datasets such as spectroscopic phase curves. Near-future observations with missions such as the James Webb Space Telescope (JWST) and Ariel will greatly improve our understanding of the atmospheres of exoplanets such as WASP-43b.
