Changes in the metallicity of gas giant planets due to pebble accretion
Changes in the metallicity of gas giant planets due to pebble accretion
复制标题
DOI：
10.1093/mnras/sty569
复制
发表时间：
2018-06-01
影响因子：
4.8
通讯作者：
Nayakshin, S.
中科院分区：
文献类型：
--
作者：
Humphries, R. J.;Nayakshin, S.
我们运行数值模拟来研究气体和尘埃颗粒对嵌入到巨大的原行星盘的气体巨行星的吸积。结果被发现取决于光盘冷却速率，行星质量，晶粒大小，和来自行星的辐射反馈。如果辐射冷却是有效的，行星会迅速地吸积气体和卵石，打开一个缺口，通常会变成大质量的棕矮星。在冷却效率低下的情况下，气体太热而不能在行星上吸积，但卵石吸积继续，行星迅速向内迁移。来自行星的辐射反馈倾向于抑制气体吸积。我们的模拟预测，金属富集的行星尘埃颗粒吸积与最终的行星质量呈负相关，根据太阳系和太阳系外巨行星的推断散装组成的观察趋势。然而，为了解释观测结果，多达30%至50%的尘埃质量应该是大颗粒的形式。
We run numerical simulations to study the accretion of gas and dust grains on to gas giant planets embedded into massive protoplanetary discs. The outcome is found to depend on the disc cooling rate, planet mass, grain size, and irradiative feedback from the planet. If radiative cooling is efficient, planets accrete both gas and pebbles rapidly, open a gap, and usually become massive brown dwarfs. In the inefficient cooling case, gas is too hot to accrete on to the planet but pebble accretion continues and the planets migrate inward rapidly. Radiative feedback from the planet tends to suppress gas accretion. Our simulations predict that metal enrichment of planets by dust grain accretion inversely correlates with the final planet mass, in accordance with the observed trend in the inferred bulk composition of Solar system and exosolar giant planets. To account for observations, however, as many as similar to 30-50 per cent of the dust mass should be in the form of large grains.