Environmental Dependence of Massive Planet Formation

大行星形成的环境依赖性

• 批准号: 0407040
• 负责人: Philip Armitage
• 金额: --
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0407040&HistoricalAwards=false
• 关键词: Environmental; Dependence; Massive; Planet; Formation

The project is developing new theoretical models for the formation of extrasolar gas giant planets in different planet formation environments. The models follow the growth of a planetary core in an evolving protoplanetary disk up to the epoch when rapid gas accretion ensues yielding a giant planet. How fast growth occurs depends upon the physical conditions in the protoplanetary disk (temperature, density etc.), and on the mobility of planetary cores and planetesimals which can migrate in orbital radius as a consequence of gravitational torques from the disk. Multidimensional numerical simulations of turbulent magnetized disks are used to characterize this mobility, and the results incorporated into one-dimensional time-dependent models for planetary growth via core accretion. The timescale for the growth of gas giant planets is being evaluated in different environments, for example around stars of different masses and metallicities. These theoretical estimates of planetary growth times may be compared to observational determinations of protoplanetary disk lifetimes to predict how the frequency of massive planet formation varies across disk environments. Existing observations are used to constrain the models, while the broader predictions will be testable using data from forthcoming ground and space-based searches for extrasolar planets.

该项目正在为不同行星形成环境中太阳系外气体巨行星的形成开发新的理论模型。该模型遵循行星核心的增长，在一个不断发展的原行星盘的时代，当快速气体吸积englomerate产生一个巨大的行星。增长的速度取决于原行星盘的物理条件（温度、密度等），以及行星核心和微行星的移动性，这些微行星可以由于来自盘的重力扭矩而在轨道半径内迁移。 湍流磁化磁盘的多维数值模拟来表征这种流动性，并将结果纳入一维随时间变化的模型，通过核心吸积行星增长。气体巨行星生长的时间尺度正在不同的环境中进行评估，例如在不同质量和金属丰度的恒星周围。 这些行星成长时间的理论估计可以与原行星盘寿命的观测测定进行比较，以预测大质量行星形成的频率如何在盘环境中变化。现有的观测结果被用来约束模型，而更广泛的预测将使用即将进行的太阳系外行星地面和太空搜索的数据进行测试。