天体核反应网络方程计算程序PP-chain

Astronomical Nuclear Reaction Network Equation Calculation Program PP-chain

核天体物理学旨在应用核物理知识来阐释宇宙天体演化进程。恒星结构与演化以及元素核合成是核天体物理学的前沿热点研究课题。核反应网络方程的建立和求解,可模拟天体演化过程中的元素核合成,包括核素丰度变化、能量的释放、反应路径等。根据主序星演化过程,建立了其内部进行的氢燃烧第一阶段质子-质子链式反应(PP-chain)的核反应网络方程。利用二阶Rosenbrock公式设计程序求解了核反应网络方程,并得到了核反应网络中核素的丰度时间演化。计算结果能够再现标准程序MESA计算结果。

Nuclear astrophysics aims to explain the evolution of cosmic body by applying nuclear physics knowledge.Stellar structure and evolution as well as elemental nucleosynthesis are hot research topics in nuclear astrophysics.The establishment and solution of the nuclear reaction network equation can simulate the nucleosynthesis of elements including the nuclide abundance change,energy release and reaction path in the process of the astronomical evolution.In this paper,a nuclear reaction network equation for the proton-proton chain reaction(PPchain)in the first stage of hydrogen burning is established according to the evolution process of the main sequence star.The second-order Rosenbrock formula is used to solve the equation of nuclear reaction network,and the time evolution of nuclide abundance in nuclear reaction network is obtained.The results can reproduce those that calculated by the standard program MESA.