Planet-planet scattering in presence of a companion star
Planet-planet scattering in presence of a companion star
复制标题
有伴星存在时的行星间散射
DOI：
10.1093/mnras/stab3602
复制
发表时间：
2021
影响因子：
4.8
通讯作者：
Gozdziewski Krzyszof
中科院分区：
文献类型：
--
作者：
Marzari Francesco;Nagasawa Makiko;Gozdziewski Krzyszof
行星-行星（P-P）散射是一种主要的动力学机制，用于解释系外行星目前的轨道分布。许多恒星属于双星系统；因此，了解这种机制在伴星存在的情况下如何运作非常重要。我们关注围绕主恒星运行的三颗行星的系统，并估计不稳定的时间尺度，发现对于内行星和双星半长轴之间具有相同比率的系统，它与开普勒周期成比例。还从模拟中导出了经验公式，以估计二元偏心率如何影响稳定区域的范围。次星的存在会影响 P-P 散射结果，导致内行星半长轴的最终分布变宽，因为行星的一些轨道能量被伴星吸收。反复接近次星也会导致双行星系统幸存的频率显着降低，特别是对于内行星半长轴的较大值而言。 Kozai 态与伴星的形成增加了可能被潮汐环化的行星数量。为了预测双星中行星可能的最终分布，我们进行了大量的模拟，其中内行星的初始半长轴是随机选择的。对于较小的双星半长轴值，较高的碰撞频率会改变最终的行星轨道分布，然而，超过 50 个天文单位似乎可以扩展到更宽的双星间隔。
Planet–planet (P–P) scattering is a leading dynamical mechanism invoked to explain the present orbital distribution of exoplanets. Many stars belong to binary systems; therefore, it is important to understand how this mechanism works in the presence of a companion star. We focus on systems of three planets orbiting the primary star and estimate the time-scale for instability, finding that it scales with the Keplerian period for systems that have the same ratio between inner planet and binary semimajor axes. An empirical formula is also derived from simulations to estimate how the binary eccentricity affects the extent of the stability region. The presence of the secondary star affects the P–P scattering outcomes, causing a broadening of the final distribution in semimajor axis of the inner planet as some of the orbital energy of the planets is absorbed by the companion star. Repeated approaches to the secondary star also cause a significant reduction in the frequency of surviving two-planet systems in particular for larger values of the inner planet semimajor axis. The formation of Kozai states with the companion star increases the number of planets that may be tidally circularized. To predict the possible final distribution of planets in binaries, we have performed a large number of simulations where the initial semimajor axis of the inner planets is chosen randomly. For small values of the binary semimajor axis, the higher frequency of collision alters the final planet orbital distributions that, however, beyond 50 au appear to be scalable to wider binary separations.
DOI：
10.1007/978-3-319-55333-7_143
发表时间：
2010
期刊：
arXiv: Earth and Planetary Astrophysics
影响因子：
--
作者：
C. Mordasini
通讯作者：
C. Mordasini
使用 Gauss-Radau 间距的高效积分器
DOI：
10.1007/978-94-009-5400-7_17
发表时间：
1985
期刊：
--
影响因子：
--
作者：
E. Everhart
通讯作者：
E. Everhart