The formation of gas giant exoplanets

过去几十年的天文观测挑战了我们对行星形成的理解。据信，巨型行星要么通过核心吸积形成（标准的行星形成理论），即尘埃颗粒逐渐增长到更大的聚集体，直到形成一个可以吸引气体包层的固体核心，要么通过盘的不稳定性形成，即大质量原恒星盘的引力破碎。标准的行星形成理论最初是用来解释我们的太阳系的，结果证明它与观测到的系外行星系统完全不同。在这个项目中，学生将使用辐射流体力学代码“Phantom”来执行一组原恒星盘模拟，以确定由盘碎片产生的原行星的特性。他将首先改进代码，包括辐射传输的影响，并开发一种跟踪算法，以了解最终进入地球的气体的特性。该项目的主要研究领域是STFC范围内的天体物理流体动力学和行星形成。

Astronomical observations in the last few decades have challenged our understanding of planet formation. It is believed that giant planets form either by core-accretion (the standard planet formation theory), i.e. the growth of dust particles to progressively larger aggregates until a solid core forms that can attract a gaseous envelope, or via disc instability, i.e. the gravitational fragmentation of massive protostellar discs. The standard planet formation theory was originally developed to explain our Solar System, which turned out to be totally different from observed exoplanetary systems. In this project, the student will use the radiative hydrodynamic code "Phantom" to perform a set of protostellar disc simulations to determine the properties of the protoplanets produced by disc fragmentation. He will first improve the code by including the effects of radiative transfer and develop a tracking algorithm to understand the properties of the gas that ends up in the planet. The main area of the project is on astrophysical hydrodynamics and planet formation that fall within the scope of STFC.