日本地球惑星科学連合2016年大会

講演情報

ポスター発表

セッション記号 P (宇宙惑星科学) » P-PS 惑星科学

[P-PS15] アルマによる惑星科学の新展開

2016年5月22日(日) 17:15 〜 18:30 ポスター会場 (国際展示場 6ホール)

コンビーナ:*百瀬 宗武(茨城大学理学部)、奥住 聡(東京工業大学大学院理工学研究科)、小林 浩(名古屋大学理学研究科)、佐川 英夫(京都産業大学理学部)、長谷川 哲夫(自然科学研究機構 国立天文台)

17:15 〜 18:30

[PPS15-P04] 円盤・惑星相互作用によるギャップ生成の定量的モデル

金川 和弘2、*武藤 恭之1田中 秀和3 (1.工学院大学基礎・教養教育部門、2.シュチェチン大学、3.東北大学・天文)

キーワード:原始惑星系円盤、円盤・惑星相互作用、円盤直接撮像

Recent high resolution observations have revealed that protoplanetary disks are rich in structures. Especially, multiple ring-like structures are discovered in the disk around HL Tau by the long baseline campaign observations of ALMA.

Such structures may be connected to the dynamical processes that occur in the disks. One interesting processes that occur in protoplanetary disks is the gravitational interaction between a (already formed) planet and the disk. As a result of disk-planet interaction, planets induce gap and spirals in the disk. If such structures are found in real observations, they strongly indicate the existence of a planet embedded in the disk. The shape of the gaps and spirals can be used to infer the physical properties of the disk and the planet. The physical parameters of disks and planets that are derived based on the disk morphology are independent from those derived from other methods. It is therefore important to understand and model the disk-planet interaction quantitatively.

In this poster, we present a series of numerical simulations and analytical theory of the gap formation by a single planet embedded in a protoplanetary disk. We quantify the shape of the gap structures in terms of the planet mass, disk scale height and disk viscosity. We first present the depth and the width of the gap can be determined by these three quantities. We have found that the gap depth is determined by a single parameter K = q2 / (h5 * alpha), where q is the mass ratio between the planet and the central star, h is the disk aspect ratio, and alpha is the disk viscosity parameter. We have also found that the gap width is determined by K' = q2 / (h3 * alpha). We have derived a simple formula that describes the gap depth and width in terms of K and K'. We apply our results to the ALMA long baseline campaign observations of the disk around HL Tau, and suggest that the planet mass is <~ 1 MJ, if the observed gap is induced by (unseen) planets in the disk. We also present the model for the detailed profiles of the gap induced by a planet, which can be compared to observations if detailed gas structures are revealed in the near future.