Impact Experiments with a New Technique for Acceleration of Projectiles to Velocities Higher Than Earth's Escape Velocity 11.2 km/s
Impact Experiments with a New Technique for Acceleration of Projectiles to Velocities Higher Than Earth's Escape Velocity 11.2 km/s
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使用新技术将射弹加速至高于地球逃逸速度 11.2 公里/秒的撞击实验
DOI：
10.1029/2009je003385
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
T. Kadono
中科院分区：
文献类型：
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作者：
A. Sakuraba;& P. H. Roberts;T. Kadono
小行星撞击地球和其他类地行星的速度可以超过10公里/S，这样的高速撞击可以对行星表面产生显著的影响。然而，由于宏观(>；∼0.1 mm)弹丸的高宽比为∼1在实验室中不易加速到10公里/S以上，因此很少有详细的实验研究。在本文中，我们证明了用大阪大学激光工程研究所的高功率激光器Gekko XII-HiPer，用直径0.1-0.3 mm的玻璃和铝弹，可以实现大于10公里/S的撞击速度。射弹的速度是根据高速X射线条纹和分幅相机拍摄的图像来估计的。炮弹与铜或LiF板靶相撞。铜板被回收进行分析。铜板上的陨石坑大小与以前较低速度的工作推断的结果相差不远。放置在铜板附近的一个钽见证板记录了每次撞击产生的大量次级陨石坑。在LiF板碰撞的情况下，我们用带条纹相机的光谱仪观测到了Li气体的两条发射线。因此，我们可以在实验室模拟速度高于10公里/S的超高速碰撞。
The impact velocities of asteroids on Earth and other terrestrial planets can be greater than 10 km/s, and impacts at these high velocities can produce significant effects on the planetary surfaces. However, since macroscopic (>∼0.1 mm) projectiles with an aspect ratio of ∼1 are not easily accelerated to more than 10 km/s in laboratories, there are few detailed experimental studies. In this paper, we demonstrate that impact velocities greater than 10 km/s can be achieved with glass and aluminum projectiles of 0.1–0.3 mm in diameter using a high‐power laser, GEKKO XII‐HIPER at Institute of Laser Engineering, Osaka University. The velocity of the projectiles is estimated based on the images taken by high‐speed X‐ray streak and framing cameras. Projectiles collide into copper or LiF plate targets. The copper plates are recovered for analysis. The sizes of craters on the copper plates are not far from the extrapolations from previous work with lower velocities. A tantalum witness plate placed near the copper plates records a large number of secondary craters from each impact. In the case of the impacts of the LiF plates, we observe two emission lines of Li gas using a spectrometer with a streak camera. Thus, we can simulate the hypervelocity impacts with velocities higher than 10 km/s in laboratories.