TESS在TOI-2000系统中发现一颗热土星内侧的迷你海王星
摘要
热木星（P < 10 d, M > 60 ）几乎总是单独环绕其恒星，但已知数百颗中仅有四颗拥有内侧伴行星。这些罕见伴行星可通过排除高偏心率潮汐迁移来约束热木星的形成历史。关于热土星质量行星的内侧伴行星所知甚少。我们在此报告TOI-2000系统的发现，其包含一颗热土星质量行星及一颗更小的内侧伴行星。迷你海王星TOI-2000 b（, ）处于3.10天轨道，热土星TOI-2000 c（, ）处于9.13天轨道。两行星均凌其宿主星TOI-2000（TIC 371188886, V = 10.98, TESS星等 = 10.36），一颗距地174 pc、富金属的（[Fe/H] = ）G型矮星。TESS在sectors 9-11与36-38观测到两行星，我们进行了地基测光、光谱与散斑成像跟进。来自CHIRON、FEROS与HARPS的径向速度使我们能通过直接质量测量确认两行星。此外，我们展示了在PyMC框架下通过哈密顿蒙特卡洛利用MIST恒星演化轨迹约束行星与恒星参数，相较传统马尔可夫链蒙特卡洛实现了更高采样效率与更短运行时间。作为类似系统中V波段最亮宿主星，TOI-2000 b与c是JWST进行大气表征的极佳候选，可潜在区分它们是否共同形成，或TOI-2000 c在迁移过程中扫集物质形成了TOI-2000 b。
引用
@article{arxiv.2209.14396,
title = {TESS spots a mini-neptune interior to a hot saturn in the TOI-2000 system},
author = {Lizhou Sha and Andrew M. Vanderburg and Chelsea X. Huang and David J. Armstrong and Rafael Brahm and Steven Giacalone and Mackenna L. Wood and Karen A. Collins and Louise D. Nielsen and Melissa J. Hobson and Carl Ziegler and Steve B. Howell and Pascal Torres-Miranda and Andrew W. Mann and George Zhou and Elisa Delgado-Mena and Felipe I. Rojas and Lyu Abe and Trifon Trifonov and Vardan Adibekyan and Sérgio G. Sousa and Sergio B. Fajardo-Acosta and Tristan Guillot and Saburo Howard and Colin Littlefield and Faith Hawthorn and François-Xavier Schmider and Jan Eberhardt and Thiam-Guan Tan and Ares Osborn and Richard P. Schwarz and Paul Strøm and Andrés Jordán and Gavin Wang and Thomas Henning and Bob Massey and Nicholas Law and Chris Stockdale and Elise Furlan and Gregor Srdoc and Peter J. Wheatley and David Barrado Navascués and Jack J. Lissauer and Keivan G. Stassun and George R. Ricker and Roland K. Vanderspek and David W. Latham and Joshua N. Winn and Sara Seager and Jon M. Jenkins and Thomas Barclay and Luke G. Bouma and Jessie L. Christiansen and Natalia Guerrero and Mark E. Rose},
journal= {arXiv preprint arXiv:2209.14396},
year = {2023}
}
备注
v3 adds RV frequency analysis; 25 pages, 11 figures, 14 tables; revision submitted to MNRAS; machine-readable tables available as ancillary files; posterior samples available from Zenodo at https://doi.org/10.5281/zenodo.7683293 and source code at https://doi.org/10.5281/zenodo.7988268