Experimental investigation of the formation of accretionary rims around chondrules and the formation of chondrite parent bodies

球粒陨石是最常见的一类陨石，它主要由两种成分组成，一种是毫米大小的固体珠子，另一种是微米大小的尘埃颗粒。对这些球粒陨石进行了矿物学、化学和同位素学的详细分析，从而获得了它们性质的详细信息。然而，在年轻的太阳系中球粒陨石母体形成的物理条件大多是未知的。球粒陨石的年龄测定表明，它们的形成可以追溯到太阳系最初的几百万年。从那时起，球粒陨石的母体基本保持不变，因此保留了它们的原始结构。因此，关于导致观测到的内部结构的物理过程的知识可以为了解星子形成期间的主要过程提供有价值的见解，例如它们的典型碰撞速度。在这里，我们建议在实验室实验中研究预球粒陨石材料的碰撞物理，并将实验结果与真实的球粒陨石进行比较。除此之外，我们还将研究细粒球粒边缘的形成，这在许多球粒陨石中经常发现，其起源仍然是一个有争议的问题。我们的调查结果将有助于确定在年轻的太阳系中较大天体形成的过程。

Chondrites are the most common class of meteorites, which mainly consist of two components, the chondrules, which are millimeter-sized solid beads, and the matrix, which consists of micrometer-sized dust grains. These chondrites have been mineralogically, chemically and isotopically very well analyzed so that detailed information of their properties is available. However, the physical conditions under which the chondrite parent bodies were formed in the young Solar System are mostly unknown. Age determination of the chondrites showed that their formation dates back to the very first few million years of our Solar System. Since then, the chondrite parent bodies have remained mostly unchanged and have, thus, preserved their pristine structures. Therefore, knowledge about the physical processes that lead to the observed internal structures can provide valuable insights into the dominant processes during the formation time of planetesimals, e.g. their typical collision velocities. Here we propose to investigate the collision physics of pre-chondritic materials in laboratory experiments and to compare the experimental outcomes with real chondritic meteorites. In addition to that, we will investigate the formation of fine-grained chondrule rims, which are frequently found in many chondrites and whose origin is still a matter of debate. The results of our investigations will help to identify the processes by which larger bodies form in the young Solar System.