Danielski Camilla, Brucalassi Anna, Benatti Serena, Campante Tiago, Delgado-Mena Elisa, Rainer Monica, Sacco Germano, Adibekyan Vardan, Biazzo Katia, Bossini Diego, Bruno Giovanni, Casali Giada, Kabath Petr, Magrini Laura, Micela Giusi, Morello Giuseppe, Palladino Pietro, Sanna Nicoletta, Sarkar Subhajit, Sousa Sérgio, Tsantaki Maria, Turrini Diego, Van der Swaelmen Mathieu
UCL Centre for Space Exochemistry Data, Fermi Avenue, Harwell Campus, Didcot, OX11 0QR UK.
Present Address: Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía s/n, 18008 Granada, Spain.
Exp Astron (Dordr). 2022;53(2):473-510. doi: 10.1007/s10686-021-09765-1. Epub 2021 Jul 13.
The Ariel mission will characterise the chemical and thermal properties of the atmospheres of about a thousand exoplanets transiting their host star(s). The observation of such a large sample of planets will allow to deepen our understanding of planetary and atmospheric formation at the early stages, providing a truly representative picture of the chemical nature of exoplanets, and relating this directly to the type and chemical environment of the host star. Hence, the accurate and precise determination of the host star fundamental properties is essential to Ariel for drawing a comprehensive picture of the underlying essence of these planetary systems. We present here a structured approach for the characterisation of Ariel stars that accounts for the concepts of homogeneity and coherence among a large set of stellar parameters. We present here the studies and benchmark analyses we have been performing to determine robust stellar fundamental parameters, elemental abundances, activity indices, and stellar ages. In particular, we present results for the homogeneous estimation of the activity indices and , and preliminary results for elemental abundances of Na, Al, Mg, Si, C, N. In addition, we analyse the variation of a planetary spectrum, obtained with Ariel, as a function of the uncertainty on the stellar effective temperature. Finally, we present our observational campaign for precisely and homogeneously characterising all Ariel stars in order to perform a meaningful choice of final targets before the mission launch.
“ Ariel ”任务将对大约一千颗凌星系外行星的大气化学和热性质进行表征。对如此大量的行星样本进行观测，将有助于加深我们对行星和大气早期形成的理解，提供系外行星化学性质的真实代表性图景，并将其与宿主恒星的类型和化学环境直接联系起来。因此，准确精确地测定宿主恒星的基本性质对于“ Ariel ”任务描绘这些行星系统的潜在本质全貌至关重要。我们在此提出一种用于表征“ Ariel ”任务恒星的结构化方法，该方法考虑了大量恒星参数之间的均匀性和一致性概念。我们在此展示了我们为确定可靠的恒星基本参数、元素丰度、活动指数和恒星年龄而进行的研究和基准分析。特别是，我们展示了活动指数 和 的均匀估计结果，以及钠、铝、镁、硅、碳、氮元素丰度的初步结果。此外，我们分析了用“ Ariel ”任务获得的行星光谱随恒星有效温度不确定性的变化。最后，我们展示了我们为精确且均匀地表征所有“ Ariel ”任务恒星而进行的观测活动，以便在任务发射前对最终目标做出有意义的选择。
