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	2012
形態種別	学術雑誌
査読	査読あり
標題	Rapid coagulation of porous dust aggregates outside the snow line: A pathway to successful icy planetesimal formation
執筆形態	共著
掲載誌名	Astrophys. J.
巻・号・頁	752,106 (18pp)頁
著者・共著者	Okuzumi, S., Tanaka, H., Kobayashi, H., and Wada, K.
概要	Rapid orbital drift of macroscopic dust particles is one of the major obstacles to planetesimal formation in protoplanetary disks. We re-examine this problem by considering the porosity evolution of dust aggregates. We apply a porosity model based on recent N-body simulations of aggregate collisions, which allows us to study the porosity change upon collision for a wide range of impact energies. We show that dust particles can evolve into highly porous aggregates (with internal densities of much less than 0.1 g cm−3) even if collisional compression is taken into account. We also show that the high porosity triggers significant acceleration in collisional growth. This suggests that formation of icy planetesimals is possible via direct collisional growth of submicron-sized icy particles.