论文标题
用软球离散元素模拟约束触点二进制（486958）ARROKOTH的最终合并
Constraining the final merger of contact binary(486958) Arrokoth with soft-sphere discrete element simulations
论文作者
论文摘要
New Horizons Mission返回了Bilobate Kuiper Belt物体（486958）ARROKOTH的惊人图像。这是一个触点二进制，由两个完整的且相对不受干扰的前身对象形成，这些对象与狭窄的接触区域相连。我们使用PKDGRAV的版本，PKDGRAV是一种n型代码，允许粒子之间的软球碰撞，对各种可能的合并方案进行建模，目的是将Arrokoth从两个Kuiper Belt对象演变为其当前触点二进制二进制二元配置。我们发现，如果两个祖细胞都是碎石堆，则影响一定很慢（小于5 m/s），并且放牧（撞击角度大于75度）才能离开完整的裂片。在紧密同步轨道中，两个物体之间的温和接触似乎最合理。
The New Horizons mission has returned stunning images of the bilobate Kuiper belt object (486958) Arrokoth. It is a contact binary, formed from two intact and relatively undisturbed predecessor objects joined by a narrow contact region. We use a version of pkdgrav, an N-body code that allows for soft-sphere collisions between particles, to model a variety of possible merger scenarios with the aim of constraining how Arrokoth may have evolved from two Kuiper belt objects into its current contact binary configuration. We find that the impact must have been quite slow (less than 5 m/s) and grazing (impact angles greater than 75 degrees) in order to leave intact lobes after the merger, in the case that both progenitor objects were rubble piles. A gentle contact between two bodies in a close synchronous orbit seems most plausible.
