Thomas N. Gautier, Natalie M. Batalha, William J. Borucki, William D. Cochran, Edward W. Dunham, Steve B. Howell, David G. Koch, David W. Latham, Geo? W. Marcy,… 展开作者
Thomas N. Gautier, Natalie M. Batalha, William J. Borucki, William D. Cochran, Edward W. Dunham, Steve B. Howell, David G. Koch, David W. Latham, Geo? W. Marcy, Lars A. Buchhave, David R. Ciardi, Michael Endl, Gabor Furesz, Howard Isaacson, Phillip MacQueen, Georgi Mandushev, Lucianne Walkowicz
The Kepler Mission was launched on March 6, 2009 to perform a photometric survey of more than 100,000 dwarf stars to search for terrestrial-size planets with the transit technique. Follow-up observations of planetary candidates identified by detection of transit-like events are needed both for identification of astrophysical phenomena that mimic planetary transits and for characterization of the true planets and planetary systems found by Kepler. We have developed techniques and protocols for detection of false planetary transits and are currently conducting observations on 177 Kepler targets that have been selected for follow-up. A preliminary estimate indicates that between 24% and 62% of planetary candidates selected for follow-up will turn out to be true planets.
We identify a set of planetary systems observed by Kepler that merit transit timing variation (TTV) analysis given the orbital periods of transiting planets, the uncertainties for their transit times and the number of transits observed during the Kepler mission. We confirm the planetary nature of 4 KOIs within multicandidate systems. We forward model each of the planetary systems identified to determine which systems are likely to yield mass constraints that may be significantly improved upon with follow-up transit observations. We find projected TTVs diverge by more than 90 minutes after 6000…
The discovery and legacy of Kepler's multi-transiting planetary systems
我们重新审视发现的第一个候选系统，包含多个过境系外行星的影响。这些系统是利用开普勒太空望远镜的数据发现的。最初的论文介绍了五个系统（Steffen et al. 2010），在该项目发布第一个开普勒行星候选者目录时发布在网上。第二年发表的一篇后续论文中介绍了对观察到的多发性骨髓瘤人群的首次广泛分析（Lissauer等人，2011 a）。多重行星凌日系统使我们能够回答与行星系的形成和动力学演化有关的各种重要问题。这两篇论文讨论了一系列广泛的主题，包括：轨道周期比的分布、行星大小比、系统结构、平均运动共振、轨道偏心率、行星验证和确认以及不同行星群的识别。他们为后来其他研究小组的许多详细研究奠定了基础。对单个多行星系统的深入研究提供了开普勒一些最重要的系外行星发现。当我们研究这些系统中的第一个的科学影响时，我们也呈现了一些围绕他们发现的人和环境的历史。
The direct detection of new extrasolar planets from high-precision photometry data is commonly based on the observation of the transit signal of the planet as it passes in front of its star. Close-in planets, however, leave additional imprints in the light curve even if they do not transit. These are the so-called phase curve variations that include ellipsoidal, reflection and beaming effects. In Millholland & Laughlin (2017), the authors scrutinized the Kepler database looking for these phase variations from non-transiting planets. They found 60 candidates whose signals were compatible with p…
Precise Radial Velocity Measurements for Kepler Giants Hosting Planetary Candidates: Kepler-91 and KOI-1894
本文介绍了利用斯巴鲁8.2米望远镜和高色散摄谱仪（HDS）对两颗开普勒演化恒星Kepler-91（KOI-2133）和KOI-1894进行径向速度跟踪观测的结果，这两颗恒星被宣布为凌日巨行星的候选者。通过对Subaru/HDS拍摄的高精度径向速度数据和开普勒任务拍摄的测光数据进行全球建模，并考虑轨道亮度调制（椭球变化，反射/发射光等）。我们独立地确认了Kepler-91中有一颗质量为0.66 M_Jup的凌日行星（Kepler-91 b），并在~1年的时间间隔内观测到了~20 m s $^{-1}$的径向速度偏差，这表明该系统中还存在另外一颗伴星。对于KOI-1894，我们检测到径向速度和光变曲线可能的相位变化，置信度为2- 3 sigma，这可以解释为由过境的亚土星质量（~0.18 M_Jup）行星引起的恒星反射运动和椭球变化。
Kepler Mission's single-band photometry suffers from astrophysical false positives, the most common of background eclipsing binaries (BEBs) and companion transiting planets (CTPs). Multi-color photometry can reveal the color-dependent depth feature of false positives and thus exclude them. In this work, we aim to estimate the fraction of false positives that are unable to be classified by Kepler alone but can be identified with their color-dependent depth feature if a reference band (z, Ks and TESS) were adopted in follow-up observation. We build up physics-based blend models to simulate multi…
Up to date planet ephemerides are becoming increasingly important as exoplanet science moves from detecting exoplanets to characterising their architectures and atmospheres in depth. In this work ephemerides are updated for 22 Kepler planets and 4 Kepler planet candidates, constituting all Kepler planets and candidates with sufficient signal to noise in the TESS 2min dataset. A purely photometric method is utilised here to allow ephemeris updates for planets even when they do not posses significant radial velocity data. The obtained ephemerides are of very high precision and at least seven yea…
Following up the Kepler field with PLATO: Transit Timing Performance
University of Warwick（华威大学）；Centre for Exoplanets and Habitability, University of Warwick（华威大学系外行星与宜居性中心）；Centre for Space Domain Awareness, University of Warwick（华威大学太空领域感知中心）；LIRA, Observatoire de Paris, Université PSL, Sorbonne Université, Université Paris Cité, CY Cergy Paris Université, CNRS（巴黎天文台、PSL大学、索邦大学、巴黎西岱大学、CY塞尔吉巴黎大学、法国国家科学研究中心LIRA实验室）；Institute for Astronomy, KU Leuven（荷语鲁汶大学天文学研究所）；Isaac Newton Group of Telescopes（艾萨克·牛顿望远镜组）
We present a comparative analysis of observations of the selected exoplanet transits obtained at the Kyiv Comet station with the database of the TESS (Transiting Exoplanet Survey Satellite) and Kepler space telescopes. The light curves obtained by the TESS and Kepler orbital telescopes were processed using a program based on the Python package Lightkurve 2.3v which is freely available in the MUST archive (Barbara A. Mikulski Archive for Space Telescopes). The ground-based observations were carried out with the 70-cm telescope AZT-8 (Lisnyky). Photometric processing of the ground-based observat…
Kepler-9 revisited 60% the mass with six times more data
开普勒9号是第一个使用凌日时间变化来确认该系统中行星的案例。在预测了戏剧性的TTV（大于一周）之后，我们基于完整的开普勒数据集重新分析了该系统。我们重新处理了开普勒-9的所有可用数据，去除了短期和长期趋势，测量了中星的时间，并将其用于系统的动力学分析。新测定的开普勒-9 b和-9 c的质量和半径改变了这些行星的性质，相对于Holman等人在2010年描述的行星（以下称为H10），它们的体积密度非常低，但相对较好（优于7%），体积密度为0.18和0.14 g cm $^3$（约为H10值的1/3）。我们仅从测光中限制质量（45.1和31.0 M $_\oplus$，分别为开普勒-9 b和-9 c），使我们能够在径向速度数据中看到外部非凌日行星的可能迹象。在$2R_\oplus$，开普勒-9 d被确定比以前建议的要大-这表明它是一颗低质量低密度的行星。H10分析和我们的新分析之间的比较表明，TTV反演中的小的形式误差可能是误导，如果数据不包括相互作用时间尺度的显着部分。
In this study, we expand the discussion of extrasolar planetary research by proposing a new approach to detecting extrasolar moons using Kepler (K2) light curves. We shaped this investigation by comparing transit light curve data of ~5000 main-sequence stars cataloged in the NASA Exoplanet Archive, the Radio Galaxy Zoo Exoplanet Explorers and the Exoplanet Follow Up Observing Program, which served as the repository to collect and analyze supplementary K2 data. By examining K2 light curves, various characteristics related to transits were modeled, which we then compared with confirmed extrasola…
The exomoon candidate Kepler-1708 b-i was recently reported using two transits of Kepler data. Supported by a 1% false-positive probability, the candidate is promising but requires follow-up observations to confirm/reject its validity. In this paper, we consider the detectability of the exomoon candidate's transit, most specifically in the next window (March 2023) using the WFC3 instrument aboard the Hubble Space Telescope (HST). Using realistic noise estimates, accounting for the visit-long trends, and propagating the model posteriors derived using the Kepler data, we perform 75 injection-rec…
A Search for Lost Planets in the Kepler Multi-planet Systems and the Discovery of the Long-period, Neptune-sized Exoplanet Kepler-150 f
在开普勒任务发现的4700颗已确认的行星和行星候选者中，绝大多数是由开普勒管道首次发现的。在管道中，在发现过境信号后，与这些过境相关的所有数据点都会被删除，从而创建一个充满漏洞的“瑞士奶酪”般的光曲线，然后用于后续的过境搜索。这些黑洞可能会使另一颗行星无法探测（或“丢失”）。我们研究了114颗恒星的样本，其中有$3+$确认的行星，以评估这种“瑞士奶酪”的影响。模拟确定了凌日行星由于凌日遮蔽而丢失的概率很低，但不可忽略，在$P=400-500$天的周期范围内丢失的$\sim3.3\%$达到平台。然后，我们对所有行星凌日进行建模，并减去每个恒星的凌日信号，恢复凌日数据点，并使用开普勒管道搜索凌日减去的（即，transit-cleaned）光变曲线。然而，管道没有发现任何可信的新过境信号。这证明了开普勒管道选择使用传输掩蔽而不是传输相减的有效性和鲁棒性。然而，对所有凌日减去数据的后续视觉搜索，这使得更容易视觉识别新的凌日，揭示了一个新的海王星大小的系外行星（开普勒-150 f）的存在和一个可能的假阳性（开普勒-208）的潜在单一凌日。开普勒-150 f（$P=637.2$天，$R_{\rm{P}}=3.64^{+0.52}_{-0.39}$ R $_{\oplus}$）的确认与$>99.998\%$的信心，使用行星多重性参数，假阳性概率分析和过境持续时间分析的组合。
It is often assumed that the "Kepler dichotomy" -- the apparent excess of planetary systems with a single detected transiting planet in the Kepler catalog -- reflects an intrinsic bimodality in the mutual inclinations of planetary orbits. After conducting 600 simulations of planet formation followed by simulated Kepler observations, we instead propose that the apparent dichotomy reflects a divergence in the amount of migration and the separation of planetary semimajor axes into distinct "clusters". We find that our simulated high-mass systems migrate rapidly, bringing more planets into orbital…
Modeling Kepler transit light curves as false positives: Rejection of blend scenarios for Kepler-9, and validation of Kepler-9d, a super-Earth-size planet in a multiple system
