Neptune's resonances in the scattered disk
Neptune's resonances in the scattered disk
复制标题
海王星在散射盘中的共振
DOI：
10.1007/s10569-019-9917-1
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发表时间：
2019
影响因子：
1.6
通讯作者：
Malhotra Renu
中科院分区：
文献类型：
--
作者：
Lan Lei;Malhotra Renu
分散的盘状天体（SDO）被认为是外太阳系中古老的剩余微行星的一小部分，这些微行星被巨行星引力分散，并主要通过捕获和粘在海王星的外部平均运动共振（MMR）中而得以生存。为了进一步理解MMR在SDO动力学中的作用，我们利用圆平面限制性三体模型的Poincaré截面，研究了大量海王星MMR在半长轴33-140 Au范围内的相空间结构.我们发现，对于对应于海王星轨道附近近日点距离的偏心率，遥远的MMR具有稳定的区域，其宽度非常大，并且与较近的MMR的尺寸相似。我们确定了一个相移的第二共振区，存在于相空间中的行星交叉偏心率，但不是在较低的偏心率，这第二共振区起着重要的作用，在延长其动态寿命的SDO的动态。我们的非微扰测量的稳定共振区的大小证实了以前的结果，并提供了一个额外的解释的突出theN：1序列的MMR超过theN：2，N：3序列和其他MMR的人口统计的SDO;我们的结果也提供了一个工具，更容易识别共振对象。
The scattered disk objects (SDOs) are thought to be a small fraction of the ancient population of leftover planetesimals in the outer Solar system that were gravitationally scattered by the giant planets and have managed to survive primarily by capture and sticking in Neptune’s exterior mean motion resonances (MMRs). In order to advance understanding of the role of MMRs in the dynamics of the SDOs, we investigate the phase space structure of a large number of Neptune’s MMRs in the semi-major axis range 33–140 au by use of Poincaré sections of the circular planar restricted three-body model for the full range of particle eccentricity pertinent to SDOs. We find that, for eccentricities corresponding to perihelion distances near Neptune’s orbit, distant MMRs have stable regions with widths that are surprisingly large and of similar size to those of the closer-in MMRs. We identify a phase-shifted second resonance zone that exists in the phase space at planet-crossing eccentricities but not at lower eccentricities; this second resonance zone plays an important role in the dynamics of SDOs in lengthening their dynamical lifetimes. Our non-perturbative measurements of the sizes of the stable resonance zones confirm previous results and provide an additional explanation for the prominence of theN: 1 sequence of MMRs over theN: 2,N: 3 sequences and other MMRs in the population statistics of SDOs; our results also provide a tool to more easily identify resonant objects.