日本地球惑星科学連合2018年大会

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[JJ] 口頭発表

セッション記号 P (宇宙惑星科学) » P-PS 惑星科学

[P-PS09] 宇宙における物質の形成と進化

2018年5月22日(火) 13:45 〜 15:15 A03 (東京ベイ幕張ホール)

コンビーナ:橘 省吾(東京大学大学院理学系研究科宇宙惑星科学機構)、三浦 均(名古屋市立大学大学院システム自然科学研究科)、野村 英子(東京工業大学理学院地球惑星科学系、共同)、大坪 貴文(宇宙航空研究開発機構 宇宙科学研究所)、座長:橘 省吾

14:30 〜 14:45

[PPS09-04] Modeling the composition of the protoplanetary disk : carbon grain destruction effect

*Chen-En Wei1Hideko Nomura1Jeong-Eun Lee2Wing-Huen Ip3 (1.Department of Earth and Planetary Sciences, Tokyo Institute of Technology、2.Department of Astronomy and Space Science, Sejong University, Republic of Korea、3.Graduate Institute of Astronomy, National Central University, Taiwan)

キーワード:protoplanetary disk, carbon depletion

The bulk composition of Earth is dramatically carbon poor compared to that of the interstellar medium, and this phenomenon extends to the asteroid belt. A gradient in the amounts of refractory carbon relative to silicate is shown in our solar system. To interpret the carbon deficit problem, we focus on two issues: (1) The carbon depletion gradient in the inner solar system. (2) Test the carbon grain destruction observationally. We assume two kinds of central stars T-tauri star and Herbig Ae star for the former and the latter issues, respectively. The results of the chemical models with and without the carbon grain destruction show significant differences especially in the inner region of the disk midplane, where CO gas is abundant and not photodissociated. Furthermore, we consider HCN and its isotopologue, H13CN, as our candidate tracer of the carbon grain destruction, and make a prediction for the HCN and H13CN line intensity maps for the ALMA observations by applying their abundance distribution into the radiative transfer model for a Herbig Ae disk. The results indicate, the difference in the HCN/H13CN line emitting regions as well as their intensity ratio are useful tracers of the carbon grain destruction. In addition, the cumulative line flux as a function of the velocity will trace the line emitting regions and the difference between the HCN and H13CN lines will also be a tracer of the carbon grain destruction.