Exploring Nucleosynthesis in Accreting Neutron Star Common Envelopes

这个项目探索了包含一颗中子星和一颗伴星的普通包络吸积双星系统中的核合成。当伴星经历其RGB阶段时，伴星的包层有可能覆盖了中子星。这使得中子星可以从伴星的包层中吸收物质，并被认为在中子星周围形成了一个吸积盘。特别是发生在吸积盘中的核合成引起了人们的极大兴趣。例如，人们认为在这些系统中可能发生了RP过程，这将有助于解释其他天体物理站点无法产生的富质子核的存在。为了了解吸积盘中的核合成，我将特别研究吸积物质如何在中子星上和外移动；新吸积物质如何与已经经历核合成的物质混合；以及吸积中子星共同包层系统对星系化学演化(GCE)的影响。我们还将探索在吸积盘中合成的物质有多少到达伴星的包层，以及当伴星经历超新星阶段或驱逐其包层时，有多少物质到达星际介质(ISM)。如果这个地点确实允许反相过程发生，那么富质子的产品可能能够到达ISM并影响GCE。我们将与维多利亚大学(加拿大)和洛斯阿拉莫斯国家实验室(美国)的合作者共同探索这些过程。

This project explores nucleosynthesis in common envelope accreting binary systems which contains a neutron star and a companion star. When the companion star undergoes its RGB phase, it is possible that the envelope of the companion star covers the neutron star. This allows the neutron star to accrete material from the companion's envelope and an accretion disk is thought to form around the neutron star.In particular, the nucleosynthesis which occurs within the accretion disk is of great interest. For example, it is thought that the rp-process may occur within these systems, which would help to explain the existence of proton rich nuclei which cannot be produced at other astrophysical sites.In order to understand the nucleosynthesis within the accretion disk, I will in particular study how the accreted material moves on and off of the neutron star; how the newly accreted material mixes with material which has already undergone nucleosynthesis; as well as the impact of accreting neutron star common envelope systems on galactic chemical evolution (GCE). We will also explore how much of the material synthesised in the accretion disk reaches the companion star's envelope, as well as how much of that material then reaches the interstellar medium (ISM) when the companion star goes through its supernova phase or expels its envelope. If this site does allow the rp-process to occur then the proton rich products may be able to reach the ISM and impact GCE. We will explore these processes jointly with our collaborators at the University of Victoria (Canada) and Los Alamos National Laboratory (USA).