The Evolution of Rotation and Magnetic Activity in 94 Aqr Aa from Asteroseismology with TESS
Travis S. Metcalfe, Jennifer L. van Saders, Sarbani Basu, Derek Buzasi, William J. Chaplin, Ricky Egeland, Rafael A. Garcia, Patrick Gaulme, Daniel Huber, Timo … 展开作者
Travis S. Metcalfe, Jennifer L. van Saders, Sarbani Basu, Derek Buzasi, William J. Chaplin, Ricky Egeland, Rafael A. Garcia, Patrick Gaulme, Daniel Huber, Timo Reinhold, Hannah Schunker, Keivan G. Stassun, Thierry Appourchaux, Warrick H. Ball, Timothy R. Bedding, Sebastien Deheuvels, Lucia Gonzalez-Cuesta, Rasmus Handberg, Antonio Jimenez, Hans Kjeldsen, Tanda Li, Mikkel N. Lund, Savita Mathur, Benoit Mosser, Martin B. Nielsen, Anthony Noll, Zeynep Celik Orhan, Sibel Ortel, Angela R. G. Santos, Mutlu Yildiz, Sallie Baliunas, Willie Soon
备注：
14 pages including 8 figures and 3 tables (updated Table 3 & Figure 6). ApJ in press
Most previous efforts to calibrate how rotation and magnetic activity depend on stellar age and mass have relied on observations of clusters, where isochrones from stellar evolution models are used to determine the properties of the ensemble. Asteroseismology employs similar models to measure the properties of an individual star by matching its normal modes of oscillation, yielding the stellar age and mass with high precision. We use 27 days of photometry from the Transiting Exoplanet Survey Satellite to characterize solar-like oscillations in the G8 subgiant of the 94 Aqr triple system. The resulting stellar properties, when combined with a reanalysis of 35 yr of activity measurements from the Mount Wilson HK project, allow us to probe the evolution of rotation and magnetic activity in the system. The asteroseismic age of the subgiant agrees with a stellar isochrone fit, but the rotation period is much shorter than expected from standard models of angular momentum evolution. We conclude that weakened magnetic braking may be needed to reproduce the stellar properties, and that evolved subgiants in the hydrogen shell-burning phase can reinvigorate large-scale dynamo action and briefly sustain magnetic activity cycles before ascending the red giant branch.
Investigating Gaia EDR3 parallax systematics using asteroseismology of Cool Giant Stars observed by Kepler, K2, and TESS I. Asteroseismic distances to 12,500 red-giant stars
Pulsating H-deficient WDs and pre-WDs observed with TESS: V. Discovery of two new DBV pulsators, WD J152738.4-450207.4 and WD 1708-871, and asteroseismology of the already known DBV stars PG 1351+489, EC 20058-5234, and EC 04207-4748
CHARA Interferometry and TESS Asteroseismology of the Core-Helium Burning Red Giant $κ$ Cyg
Sydney Institute for Astronomy, School of Physics, University of Sydney（悉尼大学物理学院天体物理研究所）；Institute for Astronomy, University of Hawai‘i（夏威夷大学天文研究所）；Sydney Informatics Hub, Core Research Facilities, University of Sydney（悉尼大学核心研究设施悉尼信息学中心）
Unveiling the properties of pulsating low-mass helium-core white dwarfs through TESS asteroseismology I. First results
Universidad Nacional de La Plata（拉普拉塔国立大学）；CONICET-UNLP（阿根廷国家科学研究委员会-拉普拉塔国立大学）；City University of New York Graduate Center（纽约市立大学研究生院）；KU Leuven（荷语鲁汶大学）；Queens College, City University of New York（纽约市立大学皇后学院）；Universitat Politècnica de Catalunya（加泰罗尼亚理工大学）；Boston University（波士顿大学）
Deep Learning Classification in Asteroseismology Using an Improved Neural Network: Results on 15000 Kepler Red Giants and Applications to K2 and TESS Data
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Tess asteroseismology of the known planet host star $λ^2$ Fornacis
凌日系外行星调查卫星（TESS）正在几乎整个天空中观测明亮的已知行星宿主恒星。这些恒星已经进行了广泛的地面观测，提供了大量的径向速度（RV）测量。在这项工作中，我们使用新的TESS光度观测的特点恒星$λ^2$天炉座，并在此之后更新的参数的轨道行星$λ^2$为b。我们测量了$λ^2$ For中的p模振荡频率，并结合非地震参数，使用恒星模型估计了恒星的基本性质。使用修订后的恒星属性和一个时间序列的档案RV数据从UCLES，HIRES和HARPS仪器跨越近20年，我们改装的轨道$λ^2$为b和搜索剩余的变异性的RV残差。我们发现$λ^2$ For的质量为$1.16\pm0.03$ M $_\odot$，半径为$1.63\pm0.04$ R $_\odot$，年龄为$6.3\pm0.9$ Gyr。该测量值和更新的RV测量值表明，对于$16.8^{+1.2}_{-1.3}$ M $_\oplus$的b，$λ^2$的质量小于文献估计值，即$\sim5$ M $_\oplus$。我们还检测到在RV测量的周期为33天，这可能是由于主机恒星的旋转。虽然先前文献对$λ^2$性质的估计是模糊的，但星震测量结果将这颗恒星牢牢地定位在亚巨星演化阶段的早期阶段。通常情况下，TESS只能提供短时间序列的光度数据，但通过使用星震学，仍然有可能对迄今为止只能从地面观察到的明亮恒星的性质提供严格的限制。这促使重新审查…
Asteroseismology of 35 Kepler and TESS $δ$ Scuti stars near the red edge of the instability strip. The limitations of $δ$ Scuti stars for dating open clusters
Global asteroseismology of 19,000 red giants in the TESS Continuous Viewing Zones
University of Sydney（悉尼大学）；University of Hawai‘i（夏威夷大学）；University of New South Wales（新南威尔士大学）；Massachusetts Institute of Technology（麻省理工学院）；National University of Singapore（新加坡国立大学）；Australian National University（澳大利亚国立大学）
Asteroseismology and interferometry of the F7V spectroscopic binary $χ$ Draconis A in the TESS CVZ
Aarhus University（奥胡斯大学）；University of Sydney（悉尼大学）；Macquarie University（麦考瑞大学）；Institute of Space Sciences (ICE, CSIC)（空间科学研究所（ICE，CSIC））；Institut d’Estudis Espacials de Catalunya (IEEC)（加泰罗尼亚空间研究学院）
Investigating Gaia EDR3 parallax systematics using asteroseismology of Cool Giant Stars observed by Kepler, K2, and TESS II. Deciphering Gaia parallax systematics using red clump stars
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Beijing Normal University（北京师范大学）；Xinjiang Astronomical Observatory, Chinese Academy of Sciences（中国科学院新疆天文台）；INAF – Osservatorio Astrofisico di Catania（意大利国家天体物理研究所卡塔尼亚天文台）
Pushing the Limit of Asteroseismic Detection for Cool Dwarfs using TESS and Deep Learning
University of Rochester（罗切斯特大学）；California Institute of Technology（加州理工学院）；University of Chicago（芝加哥大学）；Center for Astrophysics — Harvard & Smithsonian（哈佛与史密森尼天体物理中心）；Harvard University（哈佛大学）；Anton Pannekoek Institute, University of Amsterdam（阿姆斯特丹大学安东·潘内克研究所）；SRON（荷兰空间天文研究所）；Université de Moncton（蒙克顿大学）
