ワダ　コウジ   WADA Koji   和田　浩二    所属   千葉工業大学  惑星探査研究センター 惑星探査研究センター    職種   主席研究員
言語種別	日本語
発行・発表の年月	2013
形態種別	学術雑誌
査読	査読あり
標題	Impact and intrusion experiments on the deceleration of low-velocity impactors by small-body regolith
執筆形態	共著
掲載誌名	Icarus
巻・号・頁	223,222-233頁
著者・共著者	Nakamura, A. M., Setoh, M.,Wada, K., Yamashita, Y., and Sangen, K.
概要	The cratering process on granular media is common on asteroids and planetary regolith. We conducted laboratory experiments on the deceleration of projectiles with low impact velocities to understand the re-accumulation process of ejecta on small asteroids. In the impact experiments, the projectiles were decelerated mainly as a result of drag proportional to the square of the velocity. The drag coefficient was 0.9–1.5. Additionally, we found a possible term proportional to the projectile velocity corresponding to the viscous drag with a viscosity up to 2 Pa s. These forces are consistent with numerical simulations that we carried out. The penetration depth was more sensitive to the drag parameters in the case of small particles impacting a relatively small model asteroid.