Ia型超新星的公共包层星风模型的构建和应用

Type Ia supernovae (SNe Ia) play a very important role in many astrophysical fields, i.e. colmology, galaxy and stellar physics. However, many basic problems about SNe Ia are still unclear, especially about its progenitor model. At present, the optically thick wind (OTW) model is the most popular model, but there are some weaknesses in the model and some predictions from the model conflict with observations. In this project, we will construct a common-envelope wind (CEW) progenitor model, which may conquer the shortcomings of the OTW model, and show a great protential to explain other properties of SNe Ia. We will study the birth rate of SNe Ia from the CEW model. Based on the CEW model, we will study the properties of the prigenitor system at different phase and the surviving companions of SNe Ia by binary population synthesis method, and study the impact between supernova ejecta and the companions. Based on the CE model, we will study the properties of circumstellar material (CSM) around progenitor systems and calculate the X-ray, infrared and radio flux from the collision between supernova ejecta and the CSM. In addition, we will also show the distribution of the color excess of SNe Ia because of the existence of the CSM. Finally, according to the CEW model and the Atmospheric RLOF, Wind-RLOF models, we will try to conquer the issue that the birth rate of old SNe Ia from theory is much lower than that from observadions.

Ia型超新星在宇宙学、星系物理学和恒星物理学等方面都非常重要，但有关Ia型超新星的最基本的问题都没有解决，特别是与其前身星有关的问题。光学厚星风模型（OTW）是目前流行的单简并星模型，但有其自身不可克服的问题，很多预言与观测不符。本项目要构建一个既能克服OTW模型的困难，又能具有巨大潜力来解释Ia型超新星其它特性的全新模型：公共包层星风（CEW）演化模型，并给出Ia型超新星的诞生率；在此模型的基础上，我们还将研究不同演化阶段的前身星系统和残留伴星的各种积分统计特性、爆炸抛射物与伴星的相互作用；本项目将利用建立的模型研究前身星周围星周物质的分布特性，并采用大样本演化的方法给出爆炸抛射物与星周物质相互作用释放的X射线、红外和射电流量，同时研究Ia型超新星的色余分布。本项目还将结合CEW模型和Atmospheric RLOF、Wind-RLOF模型来研究年老Ia型超新星的诞生率不足的问题。

尽管Ia型超新星在现代宇宙学中有重要的应用，但其起源仍然不清楚。本项目的最主要目的就是构建一个能解释大部分Ia型超新星观测现象的前身星模型。我们成功构建了这样一个模型，我们称之为公共包层星风模型。这个模型继承了之前模型的优点，并成功克服了其缺点。. 基于此模型，我们发现两类特殊的Ia型超新星（类2002cx和SNe Ia-CSM型超新星）具有相同的起源。我们模型预言的两类超新星的诞生率和数量比与观测相符。我们还成功预言了一类介于Ia型超新星和核塌缩型超新星之间的杂交型超新星，其预言特征与SN2012ca类似。. 基于公共包层星风模型和spin-up/spin-down模型，我们对为什么有些Ia型超新星有单简并星模型预言的信号而有些没有给出了统一解释。. 我们还通过观测统计研究发现所有类型的Ia型超新星都遵从一个统一的偏振规律，这可能意味着无论Ia型超新星的前身星是什么，其爆炸模型都是一样的。