AI 中文总结
本研究通过激光模拟撞击实验推导标度关系，明确带熔融边缘微陨石坑形成于10²至10³ m/s撞击速度范围，为其形成机制提供实验约束，契合次级撞击起源及相关流体动力学不稳定性的结论。
AI 中文摘要
带熔融边缘的微陨石坑在月球和小行星的返回样品中被广泛观测到，这些特征反映了小型撞击事件的条件，但其形成所需的撞击速度尚不明确。本研究采用对岩石表面进行控制良好的激光照射作为实验类比，探究这类带熔融边缘陨石坑的形成机制，具体推导了陨石坑体积、总照射能量与热扩散相关的能量损失之间的标度关系。实验结果表明，微陨石坑的熔融边缘结构可在10²至10³ m/s的撞击速度范围内形成，该数值与部分此前认为微陨石坑起源于次级撞击事件的研究结论一致。这些发现为带熔融边缘微陨石坑的形成机制提供了实验约束，也为行星表面记录的撞击过程提供了新视角，其估算结果还与瑞利-泰勒流体动力学不稳定性产生观测到的波状边缘凸起所需的撞击速度（约10² m/s）相符。
英文摘要
Microcraters with molten rims are widely observed in returned samples from the Moon and asteroids. These features reflect the conditions of small-scale impact events, but the impact velocities required for their formation are not well understood. In this study, we use well-controlled laser irradiation on rock surfaces as an experimental analog to investigate the formation of these molten-rim craters. Specifically, we derive a scaling relation between crater volume, total irradiation energy, and energy loss associated with thermal diffusion. The experimental results indicate that molten-rim structures of microcraters can be formed in the range of $10^2$--$10^3$~m/s impact velocity. This value is consistent with some previous studies which suggested that the origin of microcraters is secondary impact events. These findings provide experimental constraints on the formation mechanisms of molten-rim microcraters and offer a new perspective on impact processes recorded on planetary surfaces. The estimated result is also consistent with the impact velocity required to produce the observed wavy rim protrusions due to a Rayleigh-Taylor hydrodynamic instability ($\sim 10^2$~m/s).
Comments16 pages, 8 figures
