TESS 调查——年轻系外行星的人口统计（TI-DYE）II：17 百万年系统 HIP 67522 中的第二颗巨行星
TESS Investigation -- Demographics of Young Exoplanets (TI-DYE) II: a second giant planet in the 17-Myr system HIP 67522
Madyson G. Barber, Pa Chia Thao, Andrew W. Mann, Andrew Vanderburg, Mayuko Mori, John H. Livingston, Akihiko Fukui, Norio Narita, Adam L. Kraus, Benjamin M. Tof… 展开作者
Madyson G. Barber, Pa Chia Thao, Andrew W. Mann, Andrew Vanderburg, Mayuko Mori, John H. Livingston, Akihiko Fukui, Norio Narita, Adam L. Kraus, Benjamin M. Tofflemire, Elisabeth R. Newton, Joshua N. Winn, Jon M. Jenkins, Sara Seager, Karen A. Collins, Joseph D. Twicken
本研究通过 TESS 和地面多波段光度测量，在 17 百万年系统 HIP 67522 中发现第二颗巨行星 HIP 67522 c，周期 14.33 天，与已知行星 b 接近 2:1 共振，并解释其先前被遗漏的原因。
摘要：
最年轻（<50 百万年）的行星对于理解行星形成和早期演化至关重要。已知 17 百万年的系统 HIP 67522 拥有一颗在紧密轨道上的巨行星（约 10 个地球半径）。在发现论文中，Rizzuto 等人（2020 年）报告了使用 TESS 在该系统中探测到一个额外的行星的单个凌星事件。在此，我们报告发现 HIP 67522 c，它与该单个凌星事件相匹配。我们通过来自 Sinistro 和 MuSCAT4 的地基多波段光度测量确认了该信号。在 14.33 天的周期下，行星 c 接近与 b（6.96 天或 2.06:1）的 2:1 平均运动共振。光变曲线在许多凌星期间显示出畸变，这与黑子穿越事件和/或耀斑一致。在行星 b 的凌星中看到的恒星活动事件较少，表明行星 c 正在穿越更活跃的纬度。此类畸变，加上 TESS 光变曲线提取中的系统效应，很可能解释了为什么行星 c 之前被遗漏。
英文摘要：
The youngest ($<$50 Myr) planets are vital to understand planet formation and early evolution. The 17 Myr system HIP 67522 is already known to host a giant ($\simeq$10$R_\oplus$) planet on a tight orbit. In the discovery paper, Rizzuto et al. 2020 reported a tentative single transit detection of an additional planet in the system using TESS. Here, we report the discovery of HIP 67522 c which matches with that single transit event. We confirm the signal with ground-based multi-wavelength photometry from Sinistro and MuSCAT4. At a period of 14.33 days, planet c is close to a 2:1 mean motion resonance with b (6.96 days or 2.06:1). The light curve shows distortions during many of the transits, which are consistent with spot crossing events and/or flares. Fewer stellar activity events are seen in the transits of planet b, suggesting that planet c is crossing a more active latitude. Such distortions, combined with systematics in the TESS light curve extraction, likely explain why planet c was previously missed.
The TESS mission has enabled discoveries of the brightest transiting planet systems around young stars. These systems are the benchmarks for testing theories of planetary evolution. We report the discovery of a mini-Neptune transiting a bright star in the AB Doradus moving group. HIP 94235 (TOI-4399, TIC 464646604) is a Vmag=8.31 G-dwarf hosting a 3.00 -0.28/+0.32 Rearth mini-Neptune in a 7.7 day period orbit. HIP 94235 is part of the AB Doradus moving group, one of the youngest and closest associations. Due to its youth, the host star exhibits significant photometric spot modulation, lithium …
We report the discovery of HIP-97166b (TOI-1255b), a transiting sub-Neptune on a 10.3-day orbit around a K0 dwarf 68 pc from Earth. This planet was identified in a systematic search of TESS Objects of Interest for planets with eccentric orbits, based on a mismatch between the observed transit duration and the expected duration for a circular orbit. We confirmed the planetary nature of HIP-97166b with ground-based radial velocity measurements and measured a mass of $M_{b} =$ 20 $\pm$ 2 $M_\bigoplus$ along with a radius of $R_{b} =$ 2.7 $\pm$ 0.1 $R_\bigoplus$ from photometry. We detected an add…
We present a systematic phase curve analysis of known transiting systems observed by the Transiting Exoplanet Survey Satellite (TESS) during year one of the primary mission. Using theoretical predictions for the amplitude of the planetary longitudinal atmospheric brightness modulation, stellar ellipsoidal distortion and Doppler boosting, as well as brightness considerations to select targets with likely detectable signals, we applied a uniform data processing and light-curve modeling framework to fit the full-orbit phase curves of 22 transiting systems with planet-mass or brown dwarf companion…
A compact multi-planet system transiting HIP 29442 (TOI-469) discovered by TESS and ESPRESSO. Radial velocities lead to the detection of transits with low signal-to-noise ratio
We present the discovery of a transiting hot Jupiter orbiting HIP 67522 ($T_{eff}\sim5650$ K; $M_* \sim 1.2 M_{\odot}$) in the 10-20 Myr old Sco-Cen OB association. We identified the transits in the TESS data using our custom notch-filter planet search pipeline, and characterize the system with additional photometry from Spitzer, spectroscopy from SOAR/Goodman, SALT/HRS, LCOGT/NRES, and SMARTS/CHIRON, and speckle imaging from SOAR/HRCam. We model the photometry as a periodic Gaussian process with transits to account for stellar variability, and find an orbital period of 6.9596$^{+0.000016}_{-0…
We report the confirmation and mass determination of three hot Jupiters discovered by the Transiting Exoplanet Survey Satellite (TESS) mission: HIP 65Ab (TOI-129, TIC-201248411) is an ultra-short-period Jupiter orbiting a bright (V=11.1 mag) K4-dwarf every 0.98 days. It is a massive 3.213 +/- 0.078 Mjup planet in a grazing transit configuration with an impact parameter of b = 1.17 +0.10/-0.08. As a result the radius is poorly constrained, 2.03 +0.61/-0.49 Rjup. The planet's distance to its host star is less than twice the separation at which it would be destroyed by Roche lobe overflow. It is …
A Ground-Based Transit Observation of the Long-Period Extremely Low-Density Planet HIP 41378 f
Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology（麻省理工学院卡弗里天体物理与空间研究所）；Center for Astrophysics | Harvard & Smithsonian（哈佛与史密森尼天体物理中心）；Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology（麻省理工学院地球、大气与行星科学系）
We present new observations of the multi-planet system HIP~41378, a bright star ($V$ = 8.9, $K_s$ = 7.7) with five known transiting planets. Observations in Campaign 5 of the K2 mission showed multiple transits of two Neptune-sized bodies and single transits of three larger planets ($R_P= 0.33R_J, 0.47R_J, 0.88 R_J$). K2 recently observed the system again in Campaign 18. We observe one new transit each of two of the larger planets, HIP41378~d and~f, giving maximal possible orbital periods of 1114 and 1084 days, respectively. Other possible periods include integer divisions of these maximum val…
Transit timing and starspot-induced transit depth variations in the $\sim$17 Myr old HIP 67522 system
University of Geneva（日内瓦大学）；University of Bern（伯尔尼大学）；European Space Agency (ESA)（欧洲空间局）；Queen Mary University of London（伦敦玛丽女王大学）；Leibniz-Institut für Astrophysik Potsdam (AIP)（波茨坦莱布尼茨天体物理研究所）
We present the bright (V$_{mag} = 9.12$), multi-planet system TOI-431, characterised with photometry and radial velocities. We estimate the stellar rotation period to be $30.5 \pm 0.7$ days using archival photometry and radial velocities. TOI-431b is a super-Earth with a period of 0.49 days, a radius of 1.28 $\pm$ 0.04 R$_{\oplus}$, a mass of $3.07 \pm 0.35$ M$_{\oplus}$, and a density of $8.0 \pm 1.0$ g cm$^{-3}$; TOI-431d is a sub-Neptune with a period of 12.46 days, a radius of $3.29 \pm 0.09$ R$_{\oplus}$, a mass of $9.90^{+1.53}_{-1.49}$ M$_{\oplus}$, and a density of $1.36 \pm 0.25$ g cm…
Netherlands Institute for Radio Astronomy, ASTRON（荷兰射电天文研究所，ASTRON）；Leibniz-Institut für Astrophysik Potsdam, AIP（波茨坦莱布尼兹天体物理研究所，AIP）；Kapteyn Astronomical Institute, University of Groningen（格罗宁根大学卡普坦天文研究所）；Institut für Physik und Astronomie, Universität Potsdam（波茨坦大学物理与天文研究所）；Anton Pannenkoek Institute for Astronomy, University of Amsterdam（阿姆斯特丹大学安东·潘农科克天文研究所）；Department of Astronomy, Stockholm University（斯德哥尔摩大学天文学系）；Geneva Observatory, Universit（日内瓦观测台，大学）
Luminaries in the Sky: The TESS Legacy Sample of Bright Stars. I. Asteroseismic detections in naked-eye main-sequence and sub-giant solar-like oscillators
Exoplanet systems with multiple transiting planets are natural laboratories for testing planetary astrophysics. One such system is HD 191939 (TOI-1339), a bright (V=9) and Sun-like (G9V) star, which TESS found to host three transiting planets (b, c, and d). The planets have periods of 9, 29, and 38 days each with similar sizes from 3 to 3.4 $R_{\oplus}$. To further characterize the system, we measured the radial velocity (RV) of HD 191939 over 415 days with Keck/HIRES and APF/Levy. We find that $M_b = 10.4 \pm 0.9 M_{\oplus}$ and $M_c = 7.2 \pm 1.4 M_{\oplus}$, which are low compared to most k…
We present the discovery of TOI-197.01, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. TOI-197 (HIP116158) is a bright (V=8.2 mag), spectroscopically classified subgiant which oscillates with an average frequency of about 430 muHz and displays a clear signature of mixed modes. The oscillation amplitude confirms that the redder TESS bandpass compared to Kepler has a small effect on the oscillations, supporting the expected yield of thousands of solar-like oscillators with TESS 2-minute cadence o…
Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present here the confirmation, based on Spitzer transit observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass ($M_*=0.77\pm0.05\,M_{\odot}$) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer…
The GAPS programme at TNG LXXI. A sub-Neptune suitable for atmospheric characterization in a multiplanet and mutually inclined system orbiting the bright K dwarf TOI-5789 (HIP 99452)
INAF - Osservatorio Astrofisico di Torino（意大利国家天体物理研究所都灵天文台）；INAF - Osservatorio Astronomico di Palermo（意大利国家天体物理研究所巴勒莫天文台）；Instituto de Astrofísica de Canarias (IAC)（加那利天体物理学研究所）；Departamento de Astrofísica, Universidad de La Laguna (ULL)（拉帕马大学天体物理学系）；INAF-Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Space Research Institute, Austrian Academy of Sciences（奥地利科学院空间研究所）
The detection of transiting exoplanets in time-series photometry requires the removal or modeling of instrumental and stellar noise. While instrumental systematics can be reduced using methods such as pixel level decorrelation, removing stellar trends while preserving transit signals proves challenging. Due to vast archives of light curves from recent transit surveys, there is a strong need for accurate automatic detrending, without human intervention. A large variety of detrending algorithms are in active use, but their comparative performance for transit discovery is unexplored. We benchmark…
Small planets are common around late-M dwarfs and can be detected through highly precise photometry by the transit method. Planets orbiting nearby stars are particularly important as they are often the best-suited for future follow-up studies. We present observations of three nearby M-dwarfs referred to as EIC-1, EIC-2, and EIC-3, and use them to search for transits and set limits on the presence of planets. On most nights our observations are sensitive to Earth-sized transiting planets, and photometric precision is similar to or better than TESS for faint late-M dwarfs of the same magnitude (…
Giant stars as known exoplanet hosts are relatively rare due to the potential challenges in acquiring precision radial velocities and the small predicted transit depths. However, these giant host stars are also some of the brightest in the sky and so enable high signal-to-noise follow-up measurements. Here we report on new observations of the bright (V ~ 3.3) giant star $ι$ Draconis ($ι$ Dra), known to host a planet in a highly eccentric ~511 day period orbit. TESS observations of the star over 137 days reveal asteroseismic signatures, allowing us to constrain the stellar radius, mass, and age…
