Roche-lobe Overflow in Eccentric Planet–Star Systems
Roche-lobe Overflow in Eccentric Planet–Star Systems
复制标题
偏心行星-恒星系统中的洛希瓣溢出
DOI：
10.3847/1538-4357/aa7a05
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
V. Kalogera
中科院分区：
文献类型：
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作者：
F. Dosopoulou;S. Naoz;V. Kalogera
许多巨大的系外行星在它们的洛希极限附近被发现，并且在轻微偏心的轨道上。在这项研究中，我们研究了这样的行星的命运，通过罗氏瓣溢出作为一个功能的物理特性的二进制组件，包括离心率和旋转行星的椭圆度。我们使用一个直接的三体积分器来计算弹道极限下的质量损失轨迹，并研究可能的结果。我们发现通过拉格朗日点L1转移的质量有三种不同的结果：（1）行星的自吸积，（2）直接撞击恒星表面，（3）围绕星星形成盘。我们探索了这三种不同区域的参数空间，发现在低偏心率下，大多数系统的质量溢出导致盘的形成，而对于高偏心率或逆行轨道，自吸积是唯一可能的结果。我们的结论是，在以前的工作中经常作出的假设，即当一个行星溢出其罗氏瓣，它是迅速中断和吸积的星星是不总是有效的。
Many giant exoplanets are found near their Roche limit and in mildly eccentric orbits. In this study, we examine the fate of such planets through Roche-lobe overflow as a function of the physical properties of the binary components, including the eccentricity and the asynchronicity of the rotating planet. We use a direct three-body integrator to compute the trajectories of the lost mass in the ballistic limit and investigate the possible outcomes. We find three different outcomes for the mass transferred through the Lagrangian point L1: (1) self-accretion by the planet, (2) direct impact on the stellar surface, and (3) disk formation around the star. We explore the parameter space of the three different regimes and find that at low eccentricities, , mass overflow leads to disk formation for most systems, while, for higher eccentricities or retrograde orbits, self-accretion is the only possible outcome. We conclude that the assumption often made in previous work that when a planet overflows its Roche lobe it is quickly disrupted and accreted by the star is not always valid.