Collaborative Research: Using Brown Dwarfs to Understand Exoplanetary Atmospheres: Spectral Inversions of an Analog Population

合作研究：利用棕矮星了解系外行星大气：模拟总体的光谱反演

• 批准号: 1909776
• 负责人: Jacqueline Faherty
• 金额: $ 40.59万
• 依托单位: American Museum Natural History
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909776&HistoricalAwards=false
• 关键词: Collaborative; Research; Using; Brown; Dwarfs

Astronomers are beginning to directly image exoplanets and obtain spectroscopic data. One of the chief barriers in interpreting the data is a complete understanding of condensate clouds. Typically, the data from exoplanet atmospheres are not good enough (and the sample size is too small) for direct determination of cloud properties. The standard technique involves 'forward-modeling' of planetary atmospheres from first principles using a grid technique. This work will use isolated, young brown dwarfs as analogs for massive exoplanet atmospheres. The team will use spectral inversion techniques on data from this population to make direct interpretations of brown dwarf atmospheres. These brown dwarfs typically have properties very similar to imaged exoplanets: temperature, luminosity, age, color, spectral features. However, they lack an obscuring parent star. This makes the spectra greatly easier to collect and allows for a much larger sample size.The team will examine a set of 26 young (5-130 Myr) isolated brown dwarfs from the same stellar associations in which large exoplanets have been discovered and imaged. They will use the BREWSTER code, developed by one of the team collaborators, to conduct spectral inversions. These inversions, along with empirical spectral energy fits and forwarding modeling using the BT SETTL code, will be used to (1) derive and compare fundamental parameters, (2) assess the dependence of cloud dynamics on environment, color and spectral features of the source object, and (3) examine compositional variations among directly-imaged exoplanets and exoplanet analogs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

天文学家开始直接为系外行星成像，并获得光谱数据。解释这些数据的主要障碍之一是对凝析云的全面理解。通常，来自系外行星大气的数据不够好(而且样本量太小)，无法直接确定云的性质。这项标准技术包括使用网格技术从基本原理出发对行星大气进行正演模拟。这项工作将使用孤立的年轻棕矮星作为大质量系外行星大气的类比。该团队将使用光谱反转技术对来自这一群体的数据进行直接解释棕矮星大气。这些棕矮星通常具有与拍摄到的系外行星非常相似的性质：温度、光度、年龄、颜色、光谱特征。然而，它们缺少一颗模糊的母星。这使得光谱更容易收集，并允许更大的样本规模。该团队将研究一组26颗年轻的(5-130 Myr)独立的棕矮星，这些矮星与发现和拍摄大型系外行星的恒星组合相同。他们将使用由团队合作者之一开发的布鲁斯特代码来进行光谱反转。这些反演以及经验光谱能量拟合和使用BT SETL代码的正向建模，将用于(1)推导和比较基本参数，(2)评估云动力学对环境、颜色和源天体光谱特征的依赖，以及(3)检查直接成像的系外行星和系外行星类似物之间的成分变化。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

A Comparative L-dwarf Sample Exploring the Interplay between Atmospheric Assumptions and Data Properties

比较 L 矮星样本，探索大气假设和数据特性之间的相互作用

• DOI: 10.3847/1538-4357/ac8f2a
• 发表时间: 2022
• 期刊: The Astrophysical Journal
• 作者: Gonzales, Eileen C.;Burningham, Ben;Faherty, Jacqueline K.;Lewis, Nikole K.;Visscher, Channon;Marley, Mark
• 通讯作者: Marley, Mark

Patchy Forsterite Clouds in the Atmospheres of Two Highly Variable Exoplanet Analogs

两个高度变化的系外行星类似物大气中的片状镁橄榄石云

• DOI: 10.3847/1538-4357/acab58
• 发表时间: 2023
• 期刊: The Astrophysical Journal
• 作者: Vos, Johanna M.;Burningham, Ben;Faherty, Jacqueline K.;Alejandro, Sherelyn;Gonzales, Eileen;Calamari, Emily;Gagliuffi, Daniella Bardalez;Visscher, Channon;Tan, Xianyu;Morley, Caroline V.
• 通讯作者: Morley, Caroline V.

Retrieval of the d/sdL7+T7.5p Binary SDSS J1416+1348AB

• DOI: 10.3847/1538-4357/abbee2
• 发表时间: 2020-12
• 期刊: The Astrophysical Journal
• 作者: Eileen C. Gonzales;B. Burningham;J. Faherty;Colleen M. Cleary;C. Visscher;M. Marley;R. Lupu;R. Fr

Cloud busting: enstatite and quartz clouds in the atmosphere of 2M2224-0158

• DOI: 10.1093/mnras/stab1361
• 发表时间: 2021-05
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: B. Burningham;J. Faherty;Eileen C. Gonzales;M. Marley;C. Visscher;R. Lupu;Josefine Gaarn

Retrieval study of cool directly imaged exoplanet 51 Eri b

冷直接成像系外行星 51 Eri b 的反演研究

• DOI: 10.1093/mnras/stad670
• 发表时间: 2023
• 期刊: Monthly Notices of the Royal Astronomical Society
• 影响因子: 4.8
• 作者: Whiteford, Niall;Glasse, Alistair;Chubb, Katy L;Kitzmann, Daniel;Ray, Shrishmoy;Phillips, Mark W;Biller, Beth A;Palmer, Paul I;Rice, Ken;Waldmann, Ingo P
• 通讯作者: Waldmann, Ingo P