On the Formation Timescale and Core Masses of Gas Giant Planets
On the Formation Timescale and Core Masses of Gas Giant Planets
复制标题
关于气态巨行星的形成时间尺度和核心质量
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
P. Armitage
中科院分区：
文献类型：
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作者：
W. Rice;P. Armitage
数值模拟表明，生长中的行星核心的迁移可能由原行星盘中的湍流波动主导，而不是由流动的任何平均特性主导。我们量化了这种随机核心迁移对巨行星在失控气体吸积开始时的形成时间尺度和核心质量的影响。对于标准的太阳星云条件，如果生长的核心以十分之几个天文单位的幅度执行随机游走，木星的形成可以加速几乎一个数量级。星子表面密度的适度降低使得木星能够在 10 Myr 内形成，初始核心质量低于 10 M⊕，这与观测限制更加一致。对于太阳系外行星系统，结果表明，核心吸积可能会在盘中形成比太阳星云金属丰度更低、寿命更短的大质量行星。
Numerical simulations show that the migration of growing planetary cores may be dominated by turbulent fluctuations in the protoplanetary disk, rather than by any mean property of the flow. We quantify the impact of this stochastic core migration on the formation timescale and core mass of giant planets at the onset of runaway gas accretion. For standard solar nebula conditions, the formation of Jupiter can be accelerated by almost an order of magnitude if the growing core executes a random walk with an amplitude of a few tenths of an AU. A modestly reduced surface density of planetesimals allows Jupiter to form within 10 Myr, with an initial core mass below 10 M⊕, in better agreement with observational constraints. For extrasolar planetary systems, the results suggest that core accretion could form massive planets in disks with lower metallicities, and shorter lifetimes, than the solar nebula.