Characterization of extrasolar planets through transmission spectroscopy

在此资助申请的框架下，我们建议在钠D线中进行太阳系外行星的透射光谱学。 钠的D1和D2线通常是冷星星光谱中的强吸收线。 在"热彗星“的初次凌日过程中，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过程中过量钠吸收的地面测量结果，这些结果有些争议。 我们建议使用我们的VLT/UVES数据对HD 189733 b和WASP-7 b的钠透射光谱的VLT/UVES数据的可行性进行彻底的调查。 我们建议研究各种方法的数据提取和准备的分析，评估的影响，碲线污染的各种方法和研究可能的影响，恒星活动的钠吸收的可能变化。 最后，我们建议使用大气环流模型加上三维辐射传输处理计算模型钠传输曲线，并将它们与现有的观测结果进行比较。

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.