Abstract
Planetesimals had repeated collisional disruption and/or accretion. As planetesimals collided each other to grow in their sizes, pressure sintering, melting and gravity differentiation of the constituent materials could cause the changes of their interiors. As a result, there could be a lot of growing bodies with heterogeneous internal structures; silicate core-porous silicate mantle body and metal core-rock mantle body. Therefore, we should consider a collisional phenomenon not only for homogenous bodies but also for core-mantle bodies to strictly study the planetary accretion process. A lot of experimental data (e.g. fragment velocity and largest fragment mass) on impact disruption have been presented by previous studies of homogeneous materials such as basalt, gypsum and ice. But we do not have any experimental data on the collisional disruption of core-mantle bodies. Therefore, we performed impact experiments on core-mantle targets in order to study the differences of fragment mass distributions, fragment velocity distributions and impact strengths between homogenous targets and core-mantle targets. We used a glass core-gypsum mantle target as a core-mantle target.
