论文标题
小身体的碰撞加热和压实：其起源和进化的约束
Collisional heating and compaction of small bodies: Constraints for their origin and evolution
论文作者
论文摘要
小体的当前特性为其起源和历史提供了重要的线索。但是，过去的碰撞处理了多少小物体，以及它们在多大程度上保留了在太阳系编队和早期演变过程中发生的过程记录的记录仍然很少。在这里，我们通过分析Jutzi等人对小体分裂的大量模拟来研究碰撞加热和压实的程度。 （2019年），它使用直径为50-400 km的多孔靶标，并研究了各种撞击速度，角度和能量。我们发现，影响处理的程度通常比以前认为较小物体的研究中发现的程度（例如Jutzi等，2017； Schwartz等，2018）。但是，在影响处理方面存在明显的二分法：逃避的材料总是比与最大残留物结合的材料更强的加热。假设它们起源于同一母体，那么最近访问的小行星Ryugu和Bennu之间观察到的差异可以用材料的不同位置来解释，最终在原始父母中形成了这些小行星。我们的结果还提供了对彗星核的初始大小的约束。
The current properties of small bodies provide important clues to their origin and history. However, how much small bodies were processed by past collisions and to what extent they retain a record of processes that took place during the formation and early evolution of the Solar System is still poorly understood. Here we study the degree of collisional heating and compaction by analysing the large set of previous simulations of small body break-ups by Jutzi et al. (2019), which used porous targets of 50 - 400 km in diameter and investigated a large range of impact velocities, angles as well as energies. We find that the degree of impact processing is generally larger than found in previous studies which considered smaller objects (e.g. Jutzi et al., 2017; Schwartz et al., 2018). However, there is a clear dichotomy in terms of impact processing: the escaping material always experiences stronger heating than the material bound to the largest remnant. Assuming they originate from the same parent body, some of the observed differences between the recently visited asteroids Ryugu and Bennu may be explained by a different location of the material eventually forming these asteroids in the original parent body. Our results also provide constraints on the initial size of cometary nuclei.
