大样本恒星演化研究组知识库

介绍了行星形成涉及到的几个重要阶段，如行星迁移、核吸积和大气逃逸的基本物理过程和数值模拟研究现状。行星迁移会影响行星的轨道偏心率和倾角，并改变原行星盘的结构；核吸积是决定行星演化为类地行星或者类木行星的关键因素；大气逃逸对行星的气候和演化产生重要影响。这些过程均涉及到复杂的辐射磁流体动力学过程，早期的理论研究往往采用很多人为的简化假设。随着超级计算机计算能力的提高和磁流体数值模拟算法的日渐成熟，人们已经可以对这类复杂的非线性动力学问题开展直接的数值模拟研究，克服了早期理论研究中人为假设的局限。但是，目前人们开展的研究主要基于磁流体动力学数值模拟，对辐射转移如何影响磁流体动力学过程的研究还比较欠缺。强调了进行辐射磁流体动力学数值模拟的必要性和紧迫性。针对辐射磁流体数值模拟程序的开发，从辐射转移，磁场的处理，吸积盘的自引力、三维效应、非理想效应和尘埃的效应等方面提出了相应的技术需求。介绍了本研究领域内发展辐射磁流体数值模拟的策略。

This paper review our current understandings in some important stages of planet formation, including planet migration, core accretion, and atmospheric escape. Planet-disk interaction leads to planet migration, which can significantly influence the planet’s orbital properties as well as the disk structure. The core accretion process largely determines the destiny of growing planet embryos: to become a gas giant or a terrestrial planets. The process of atmospheric escape is strongly connected to the planetary climate and potentially origin of life. All these stages involve complex radiative magnetohydrodynamic (MHD) processes.With growing computational power and the advance of numerical algorithms, we now in an era of using computational methods to solve highly nonlinear dynamical problems, alleviating the limitation of earlier times. While computational MHD is towards its maturity, efforts that aim to incorporate radiative transfer into MHD processes are still in its infancy. This paper stresses the necessity of radiation MHD studies in the field of planet formation. We also describe the scientific demand on the capability of radiation MHD codes, and strategies for developing radiation MHD codes in China for planet formation applications.