Characterization of extrasolar planets through transmission spectroscopy

在这项资金申请的框架内，我们建议执行太阳系外行星在钠D线上的透射谱。钠D1线和D2线通常是一颗凉爽恒星光谱中的强吸收线。在“热木星”的初次凌日期间，行星大气中存在的任何钠都会导致额外的吸收信号。虽然最初是从太空进行的，但最近发表了一些关于行星凌日期间过量钠吸收的地面测量结果，但结果有些争议。我们建议使用我们在HD189733b和WASP-7b上的VLT/UVES数据来彻底研究用于钠透射谱的VLT/UVES数据的可行性。我们建议研究数据提取和准备的各种分析方法，用各种方法评估大地线污染的影响，并研究恒星活动对钠吸收可能变化的影响。最后，我们建议使用大气环流模式和三维辐射传输处理相结合的方法来计算模型的钠传输曲线，并将其与现有的观测值进行比较。

In the framework of this funding application we propose to perform transmission spectroscopy of extrasolar planets in the sodium D lines. The sodium D1 and D2 lines are -- normally -- strong absorption lines in the spectrum of a cool star. During the primary transit of a ``Hot Jupiter'' any sodium present in the planetary atmosphere will lead to an additional absorption signal.While originally carried out and pioneered from space, recently a number of ground-based measurements of excess sodium absorption during planetary transits have been published with somewhat controversial results. We propose use our VLT/UVES data on HD189733b and WASP-7b for a thorough investigation of the feasibility of VLT/UVES data for sodium transmission spectroscopy. We propose to study various methods of analysis for the data extraction and preparation, assess the influence of telluric line contamination with various methods and study the possible influence of stellar activity on possible changes in the sodium absorption. Finally we propose to use atmospheric circulation models coupled with a 3D-radiative transfer treatment to compute model sodium transmission curves and compare them to the available observations.