论文标题
在不断发展的低质量和太阳能恒星的潮汐耗散,并预测行星轨道衰减
Tidal dissipation in evolving low-mass and solar-type stars with predictions for planetary orbital decay
论文作者
论文摘要
我们在整个演变中研究质量为$ 0.1-1.6 m_ \ odot $的恒星中的潮汐消散,包括作用于对流区域中平衡潮汐和惯性波的湍流有效粘度,以及辐射区域内的内部重力波。我们考虑了一系列恒星进化模型,并结合了基于最新模拟在平衡潮汐上的频率依赖性有效粘度。我们比较了用常规平衡潮获得的潮流和耗散,这在对流区域严格无效,发现后者通常过度预测耗散的损失为2-3。惯性波的耗散是使用频率平均形式主义对逼真的恒星结构进行计算的,这是主序列上二元循环和同步的主要机制。辐射区重力波的耗散假设这些波被完全阻尼(例如,通过波破裂),是行星轨道衰变的主要机制。我们计算出波浪破裂所需的关键行星质量与恒星质量和年龄的函数,并表明该机制预测了许多热木星的破坏,但可能不会在主序列上进行地球质量行星。我们将结果应用于恒星进化后的潮汐质量因素,以及潮汐进化时尺度,热木星的轨道衰减,以及二进制恒星的自旋同步和循环化。我们还为由于潮汐驱动的轨道衰变而导致的热木星腐烂,可以预测过渡时间的变化,而NGT,苔丝或柏拉图可能会检测到。
We study tidal dissipation in stars with masses in the range $0.1-1.6 M_\odot$ throughout their evolution, including turbulent effective viscosity acting on equilibrium tides and inertial waves in convection zones, and internal gravity waves in radiation zones. We consider a range of stellar evolutionary models and incorporate the frequency-dependent effective viscosity acting on equilibrium tides based on the latest simulations. We compare the tidal flow and dissipation obtained with the conventional equilibrium tide, which is strictly invalid in convection zones, finding that the latter typically over-predicts the dissipation by a factor of 2-3. Dissipation of inertial waves is computed using a frequency-averaged formalism accounting for realistic stellar structure for the first time, and is the dominant mechanism for binary circularization and synchronization on the main sequence. Dissipation of gravity waves in the radiation zone assumes these waves to be fully damped (e.g.~by wave breaking), and is the dominant mechanism for planetary orbital decay. We calculate the critical planetary mass required for wave breaking as a function of stellar mass and age, and show that this mechanism predicts destruction of many hot Jupiters but probably not Earth-mass planets on the main sequence. We apply our results to compute tidal quality factors following stellar evolution, and tidal evolutionary timescales, for the orbital decay of hot Jupiters, and the spin synchronization and circularization of binary stars. We also provide predictions for shifts in transit arrival times due to tidally-driven orbital decay of hot Jupiters that may be detected with NGTS, TESS or PLATO.