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标题：Formation of close-in super-Earths in evolving protoplanetary disks due to disk winds
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作者：Masahiro Ogihara ; Eiichiro Kokubo ; Takeru K. Suzuki 等
期刊名称：Astronomy & Astrophysics
印刷版ISSN：0004-6361
电子版ISSN：1432-0746
出版年度：2018
卷号：615
DOI：10.1051/0004-6361/201832720
语种：English
出版社：EDP Sciences
摘要：Context.Planets with masses larger than about 0.1 M⊕undergo rapid inward migration (type I migration) in a standard protoplanetary disk. Recent magnetohydrodynamical simulations revealed the presence of magnetically driven disk winds, which would alter the disk profile and the type I migration in the close-in region.Aims.We investigate orbital evolution of planetary embryos in disks that viscously evolve under the effects of disk winds. The aim is to discuss effects of altered disk profiles on type I migration. In addition, we aim to examine whether observed distributions of close-in super-Earths can be reproduced by simulations that include effects of disk winds.Methods.We performN-body simulations of super-Earth formation from planetary embryos, in which a recent model for disk evolution is used. We explore a wide range of parameters and draw general trends. We also carry outN-body simulations of close-in super-Earth formation from embryos in such disks under various conditions.Results.We find that the type I migration is significantly suppressed in many cases. Even in cases in which inward migration occurs, the migration timescale is lengthened to 1 Myr, which mitigates the type I migration problem. This is because the gas surface density is decreased and has a flatter profile in the close-in region due to disk winds. We find that when the type I migration is significantly suppressed, planets undergo late orbital instability during the gas depletion, leading to a non-resonant configuration. We also find that observed distributions of close-in super-Earths (e.g., period ratio, mass ratio) can be reproduced. In addition, we show that in some results of simulations, systems with a chain of resonant planets, like the TRAPPIST-1 system, form.
关键词：Key wordsenplanets and satellites: formationprotoplanetary disksplanet-disk interactionsmethods: numerical