TESS-Keck 巡天. XIX. 一颗温暖的凌日次土星质量行星和一颗非凌日土星质量行星绕类太阳恒星运行
The TESS-Keck Survey. XIX. A Warm Transiting Sub-Saturn Mass Planet and a non-Transiting Saturn Mass Planet Orbiting a Solar Analog
Michelle L. Hill, Stephen R. Kane, Paul A. Dalba, Mason MacDougall, Tara Fetherolf, Zhexing Li, Daria Pidhorodetska, Natalie M. Batalha, Ian J. M. Crossfield, C… 展开作者
Michelle L. Hill, Stephen R. Kane, Paul A. Dalba, Mason MacDougall, Tara Fetherolf, Zhexing Li, Daria Pidhorodetska, Natalie M. Batalha, Ian J. M. Crossfield, Courtney Dressing, Benjamin Fulton, Andrew W. Howard, Daniel Huber, Howard Isaacson, Erik A Petigura, Paul Robertson, Lauren M. Weiss, Aida Behmard, Corey Beard, Ashley Chontos, Fei Dai, Steven Giacalone, Lea A. Hirsch, Rae Holcomb, Jack Lubin, Andrew W. Mayo, Teo Mocnik, Joseph M. Akana Murphy, Alex S. Polanski, Lee J. Rosenthal, Ryan A. Rubenzahl, Nicholas Scarsdale, Emma V. Turtelboom, Judah Van Zandt, Allyson Bieryla, David R. Ciardi, Jason D. Eastman, Ben Falk, Katharine M. Hesse, David W. Latham, John Livingston, Rachel A. Matson, Elisabeth Matthews, George R. Ricker, Alexander Rudat, Joshua E. Schlieder, S. Seager, Joshua N. Winn
备注：
Accepted for publication in The Astronomical Journal. 15 pages, 7 figures
The Transiting Exoplanet Survey Satellite (TESS) continues to dramatically increase the number of known transiting exoplanets, and is optimal for monitoring bright stars amenable to radial velocity (RV) and atmospheric follow-up observations. TOI-1386 is a solar-type (G5V) star that was detected via TESS photometry to exhibit transit signatures in three sectors with a period of 25.84 days. We conducted follow-up RV observations using Keck/HIRES as part of the TESS-Keck Survey (TKS), collecting 64 RV measurements of TOI-1386 with the HIRES spectrograph over 2.5 years. Our combined fit of the TOI-1386 photometry and RV data confirm the planetary nature of the detected TESS signal, and provide a mass and radius for planet b of $0.148\pm0.019$ $M_J$ and $0.540\pm0.017$ $R_J$, respectively, marking TOI-1386 b as a warm sub-Saturn planet. Our RV data further reveal an additional outer companion, TOI-1386 c, with an estimated orbital period of 227.6 days and a minimum mass of $0.309\pm0.038$ $M_J$. The dynamical modeling of the system shows that the measured system architecture is long-term stable, although there may be substantial eccentricity oscillations of the inner planet due to the dynamical influence of the outer planet.
We present the discovery of two new transiting extrasolar planet candidates identified as TOI-1296.01 and TOI-1298.01 by the Transiting Exoplanet Survey Satellite (TESS). The planetary nature of these candidates has been secured with the SOPHIE high-precision spectrograph through the measurement of the companion's mass with the radial velocity method. Both planets are similar to Saturn in mass and have similar orbital periods of a few days. They, however, show discrepant radii and therefore different densities. The radius discrepancy might be explained by the different levels of irradiation by…
We report the discovery and confirmation of the planetary system TOI-1288. This late G dwarf harbours two planets: TOI-1288 b and TOI-1288 c. We combine TESS space-borne and ground-based transit photometry with HARPS-N and HIRES high-precision Doppler measurements, which we use to constrain the masses of both planets in the system and the radius of planet b. TOI-1288~b has a period of $2.699835^{+0.000004}_{-0.000003}$ d, a radius of $5.24 \pm 0.09$ R$_\oplus$, and a mass of $42 \pm 3$ M$_\oplus$, making this planet a hot transiting super-Neptune situated right in the Neptunian desert. This de…
We report on the discovery and validation of TOI 813b (TIC 55525572 b), a transiting exoplanet identified by citizen scientists in data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by the Planet Hunters TESS project. The host star is a bright (V = 10.3 mag) subgiant ($R_\star=1.94\,R_\odot$, $M_\star=1.32\,M_\odot$). It was observed almost continuously by TESS during its first year of operations, during which time four individual transit events were detected. The candidate passed all the standard light curve-based vetting checks, and ground-based fol…
We report the discovery of NGTS-11 b (=TOI-1847 b), a transiting Saturn in a 35.46-day orbit around a mid K-type star (Teff=5050 K). We initially identified the system from a single-transit event in a TESS full-frame image light-curve. Following seventy-nine nights of photometric monitoring with an NGTS telescope, we observed a second full transit of NGTS-11 b approximately one year after the TESS single-transit event. The NGTS transit confirmed the parameters of the transit signal and restricted the orbital period to a set of 13 discrete periods. We combined our transit detections with precis…
We report the detection of a Saturn-size exoplanet orbiting HD 332231 (TOI 1456) in light curves from the Transiting Exoplanet Survey Satellite (TESS). HD 332231, an F8 dwarf star with a V-band magnitude of 8.56, was observed by TESS in Sectors 14 and 15. We detect a single-transit event in the Sector 15 presearch data conditioning (PDC) light curve. We obtain spectroscopic follow-up observations of HD 332231 with the Automated Planet Finder, Keck I, and SONG telescopes. The orbital period we infer from the radial velocity (RV) observations leads to the discovery of another transit in Sector 1…
During the TESS prime mission, 74% of the sky area will only have an observational baseline of 27 days. For planets with orbital periods longer than 13.5 days, TESS can only capture one or two transits, and the planet ephemerides will be difficult to determine from TESS data alone. Follow-up observations of transits of these candidates will require precise ephemerides. We explore the use of existing ground-based wide-field photometric surveys to constrain the ephemerides of the TESS single-transit candidates, with a focus on the Kilodegree Extremely Little Telescope (KELT) survey. We insert si…
We report the discovery of TOI-1268b, a transiting Saturn-mass planet from the TESS space mission. With an age of less than one Gyr, derived from various age indicators, TOI-1268b is the youngest Saturn-mass planet known to date and contributes to the small sample of well characterised young planets. It has an orbital period of $P\,=\,8.1577080\pm0.0000044$ days, and transits an early K dwarf star with a mass of $M_\star$ = $ 0.96 \pm 0.04$ $M_{\odot}$, a radius of $R_\star$ = $ 0.92 \pm 0.06$ $R_{\odot}$, an effective temperature of $T_\mathrm{eff}\,=\,5300\pm100$ K, and a metallicity of $0.3…
We present the discovery of TOI-197.01, the first transiting planet identified by the Transiting Exoplanet Survey Satellite (TESS) for which asteroseismology of the host star is possible. TOI-197 (HIP116158) is a bright (V=8.2 mag), spectroscopically classified subgiant which oscillates with an average frequency of about 430 muHz and displays a clear signature of mixed modes. The oscillation amplitude confirms that the redder TESS bandpass compared to Kepler has a small effect on the oscillations, supporting the expected yield of thousands of solar-like oscillators with TESS 2-minute cadence o…
We report the discovery of ten short-period giant planets (TOI-2193A b, TOI-2207 b, TOI-2236 b, TOI-2421 b, TOI-2567 b, TOI-2570 b, TOI-3331 b, TOI-3540A b, TOI-3693 b, TOI-4137 b). All of the planets were identified as planet candidates based on periodic flux dips observed by NASA's Transiting Exoplanet Survey Satellite (TESS). The signals were confirmed to be from transiting planets using ground-based time-series photometry, high angular resolution imaging, and high-resolution spectroscopy coordinated with the TESS Follow-up Observing Program. The ten newly discovered planets orbit relativel…
Measurements of exoplanetary orbital obliquity angles for different classes of planets are an essential tool in testing various planet formation theories. Measurements for those transiting planets on relatively large orbital periods ($P$\,$>$\,10\,d) present a rather difficult observational challenge. Here we present the obliquity measurement for the warm sub-Saturn planet HD\,332231\,b, which was discovered through Transiting Exoplanet Survey Satellite (TESS) photometry of sectors 14 and 15, on a relatively large orbital period (18.7\,d). Through a joint analysis of previously obtained spectr…
We present the discovery of a pair of transiting giant planets, TOI-216b and c, using four sectors of TESS photometry. TOI-216 is a $0.87 M_{\odot}$ dwarf orbited by two transiters with radii of $8.2 R_{\oplus}$ and $11.3 R_{\oplus}$, and periods of $17.01$d and $34.57$d, respectively. Anti-correlated TTVs are clearly evident indicating that the transiters orbit the same star and interact via a near 2:1 mean motion resonance. By fitting the TTVs with a dynamical model, we infer masses of $26_{-11}^{+24} M_{\oplus}$ and $190_{-80}^{+220} M_{\oplus}$, establishing that the objects are planetary …
We report on the discovery of a hot Saturn-sized planet (9.916 +/- 0.985 R_earth) around a late F star, EPIC 246865365, observed in Campaign 13 of the K2 mission. We began studying this planet candidate because prior to the release of Gaia DR2, the host star was thought to have been a member (> 90% membership probability) of the approximately 1 Gyr open cluster NGC 1817 based on its kinematics and photometric distance. We identify the host star (among three stars within the K2 photometric aperture) using seeing-limited photometry and rule out false positive scenarios using adaptive optics imag…
We present here a validation of sub-Saturn exoplanet TOI-181b orbiting a K spectral type star TOI-181 (Mass: 0.822 $\pm$ 0.04 M$_{\odot}$, Radius: 0.745 $\pm$ 0.02 R$_{\odot}$, Temperature: 4994 $\pm$ 50 K) as a part of Validation of Transiting Exoplanets using Statistical Tools (VaTEST) project. TOI-181b is a planet with radius 6.95 $\pm$ 0.08 R$_{\oplus}$, mass 46.16 $\pm$ 2.71 M$_{\oplus}$, orbiting in a slightly eccentric orbit with eccentricity 0.15 $\pm$ 0.06 and semi-major axis of 0.054 $\pm$ 0.004 AU, with an orbital period of 4.5320 $\pm$ 0.000002 days. The transit photometry data was…
The WASP-148 planetary system has a rare architecture with a transiting Saturn-mass planet on a tight orbit which is accompanied by a slightly more massive planet on a nearby outer orbit. Using new space-born photometry and ground-based follow-up transit observations and data available in literature, we performed modeling that accounts for gravitational interactions between both planets. Thanks to the new transit timing data for planet b, uncertainties of orbital periods and eccentricities for both planets were reduced relative to previously published values by a factor of 3-4. Variation in tr…
We report the discovery of a warm sub-Saturn, TOI-257b (HD 19916b), based on data from NASA's Transiting Exoplanet Survey Satellite (TESS). The transit signal was detected by TESS and confirmed to be of planetary origin based on radial velocity observations. An analysis of the TESS photometry, the Minerva-Australis, FEROS, and HARPS radial velocities, and the asteroseismic data of the stellar oscillations reveals that TOI-257b has a mass of $M_P=0.138\pm0.023$\,$\rm{M_J}$ ($43.9\pm7.3$\,$M_{\rm \oplus}$), a radius of $R_P=0.639\pm0.013$\,$\rm{R_J}$ ($7.16\pm0.15$\,$R_{\rm \oplus}$), bulk densi…
A Pair of Warm Saturn-mass Planets near the 2:1 Mean Motion Resonance around TOI-3850
University of British Columbia（不列颠哥伦比亚大学）；McGill University（麦吉尔大学）；Vanderbilt University（范德堡大学）；NASA Ames Research Center（美国宇航局艾姆斯研究中心）；University of Chicago（芝加哥大学）；Gemini Observatory/NSF NOIRLab（吉米天文台/美国国家光学红外天文研究实验室）
The imminent launch of space telescopes designed to probe the atmospheres of exoplanets has prompted new efforts to prioritise the thousands of transiting planet candidates for follow-up characterisation. We report the detection and confirmation of TOI-1842b, a warm Saturn identified by TESS and confirmed with ground-based observations from Minerva-Australis, NRES, and the Las Cumbres Observatory Global Telescope. This planet has a radius of $1.04^{+0.06}_{-0.05}\,R_{Jup}$, a mass of $0.214^{+0.040}_{-0.038}\,M_{Jup}$, an orbital period of $9.5739^{+0.0002}_{-0.0001}$ days, and an extremely lo…
The Orbital Eccentricity--Radius Distribution for Warm, Single Planets in TESS
University of Southern Queensland（南昆士兰大学）；University of Chicago（芝加哥大学）；University of Illinois at Urbana-Champaign（伊利诺伊大学厄巴纳-香槟分校）；National Center for Supercomputing Applications（国家超级计算应用中心）；Center for Astrophysics | Harvard & Smithsonian（哈佛-史密森天体物理中心）；NASA Exoplanet Science Institute-Caltech/IPAC（NASA系外行星科学研究所/加州理工学院IPAC）；NASA Ames Research Center（NASA艾姆斯研究中心）
We report the discovery of the transiting exoplanet NGTS-12b by the Next Generation Transit Survey (NGTS). The host star, NGTS-12, is a V=12.38 mag star with an effective temperature of T$_{\rm eff}$=$5690\pm130$ K. NGTS-12b orbits with a period of $P=7.53$d, making it the longest period planet discovered to date by the main NGTS survey. We verify the NGTS transit signal with data extracted from the TESS full-frame images, and combining the photometry with radial velocity measurements from HARPS and FEROS we determine NGTS-12b to have a mass of $0.208\pm0.022$ M$_{J}$ and a radius of $1.048\pm…
We report the discovery of two short-period Saturn-mass planets, one transiting the G subgiant TOI-954 (TIC 44792534, $ V = 10.343 $, $ T = 9.78 $) observed in TESS sectors 4 and 5, and one transiting the G dwarf K2-329 (EPIC 246193072, $ V = 12.70 $, $ K = 10.67 $) observed in K2 campaigns 12 and 19. We confirm and characterize these two planets with a variety of ground-based archival and follow-up observations, including photometry, reconnaissance spectroscopy, precise radial velocity, and high-resolution imaging. Combining all available data, we find that TOI-954 b has a radius of $0.852_{-…
Searching for GEMS: TOI-5916 b & TOI-6158 b are two Saturn-density planets orbiting M2 dwarfs
University of California, Irvine（加州大学尔湾分校）；Carnegie Institution for Science（卡内基科学研究所）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；U.S. National Science Foundation, National Optical-Infrared Astronomy Research Laboratory（美国国家科学基金会，国家光学-红外天文研究实验室）；University of Wyoming（怀俄明大学）；Las Campanas Observatory, Carnegie Observatories（拉斯坎帕纳斯天文台，卡内基观测站）
We present an optical-to-infrared transmission spectrum of the inflated sub-Saturn KELT-11b measured with the Transiting Exoplanet Survey Satellite (TESS), the Hubble Space Telescope (HST) Wide Field Camera 3 G141 spectroscopic grism, and the Spitzer Space Telescope (Spitzer) at 3.6 $μ$m, in addition to a Spitzer 4.5 $μ$m secondary eclipse. The precise HST transmission spectrum notably reveals a low-amplitude water feature with an unusual shape. Based on free retrieval analyses with varying molecular abundances, we find strong evidence for water absorption. Depending on model assumptions, we a…
NASA's Transiting Exoplanet Survey Satellite (TESS) mission promises to improve our understanding of hot Jupiters by providing an all-sky, magnitude-limited sample of transiting hot Jupiters suitable for population studies. Assembling such a sample requires confirming hundreds of planet candidates with additional follow-up observations. Here, we present twenty hot Jupiters that were detected using TESS data and confirmed to be planets through photometric, spectroscopic, and imaging observations coordinated by the TESS Follow-up Observing Program (TFOP). These twenty planets have orbital period…
University of California, Los Angeles（加州大学洛杉矶分校）；Caltech/IPAC（加州理工学院/IPAC）；Carnegie Science Observatories（卡内基科学天文台）；The University of North Carolina at Chapel Hill（北卡罗来纳大学教堂山分校）；Department of Physics and Astronomy, The University of North Carolina at Chapel Hill（北卡罗来纳大学教堂山分校物理与天文学系）；Department of Astronomy and Astrophysics, University of California, Santa Cruz（加州大学圣克鲁斯分校天文与天体物理学系）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理科学系）
Searching for GEMS: Three warm Saturns and a super-Jupiter orbiting four early M-dwarfs
University of California, Irvine（加州大学尔湾分校）；Carnegie Institution for Science（卡内基科学机构）；Southeastern Universities Research Association（东南大学研究协会）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）
The EBLM Project - XIX. The absence of radius inflation in a homogeneous analysis of 66 Northern low-mass eclipsing binaries
University of Birmingham（伯明翰大学）；The Ohio State University（俄亥俄州立大学）；Center for Astrophysics, Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Keele University（基尔大学）；Thüringer Landessternwarte Tautenburg（图林根州陶滕堡天文台）；Tsung-Dao Lee Institute, Shanghai Jiao Tong University（上海交通大学李政道研究所）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯-马赛大学）；Queen Mary University of London（伦敦玛丽女王大学）；Magdalen College, University of Oxford（牛津大学莫德林学院）；Universidad Nacional Autónoma de México, Instituto de Astronomía（墨西哥国立自治大学天文学研究所）；Hobart and William Smith Colleges（霍巴特和威廉史密斯学院）；Institut d’Astrophysique de Paris, CNRS, UMR 7095, Sorbonne Université（巴黎天体物理学研究所）；Centre for Exoplanets and Habitability, University of Warwick（华威系外行星与宜居性中心）；Department of Physics, University of Warwick（华威大学物理系）；Uppsala University（乌普萨拉大学）；Univ. Grenoble Alpes, CNRS, IPAG（格勒诺布尔阿尔卑斯大学）；Institut für Weltraumforschung, Deutsches Zentrum für Luft- und Raumfahrt（德国航空航天中心空间研究所）；European Space Agency (ESA), European Space Astronomy Centre (ESAC)（欧洲航天局欧洲空间天文中心）；Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University（奥胡斯大学恒星天体物理学中心）；University of Glasgow（格拉斯哥大学）
Warm, large exoplanets with 10-100 day orbital periods pose a major challenge to our understanding of how planetary systems form and evolve. Although high eccentricity tidal migration has been invoked to explain their proximity to their host stars, a handful reside in or near orbital resonance with nearby planets, suggesting a gentler history of in situ formation or disk migration. Here we confirm and characterize a pair of warm, large exoplanets discovered by the TESS Mission orbiting K-dwarf TOI-216. Our analysis includes additional transits and transit exclusion windows observed via ground-…
Young exoplanets are snapshots of the planetary evolution process. Planets that orbit stars in young associations are particularly important because the age of the planetary system is well constrained. We present the discovery of a transiting planet larger than Neptune but smaller than Saturn in the 45 Myr Tucana-Horologium young moving group. The host star is a visual binary, and our follow-up observations demonstrate that the planet orbits the G6V primary component, DS Tuc A (HD 222259A, TIC 410214986). We first identified transits using photometry from the Transiting Exoplanet Survey Satell…
