摘要:2015年4月位于欧洲核子中心的大型强子对撞机( )开始新一轮更高能量运行,每年可产生约 个 介子衰变事例。 介子具有不同于其它重夸克介子的特性,因此对其衰变过程的研究具有重要科学价值:不仅可以帮助我们探究重物理动力学,检验标准模型理论,而且可以为我们理解其末态轻标量介子产物的物理特性提供良好平台。
我们采用 因子化方法对两体无粲非轻衰变 过程进行研究,探索其中所涉及的微扰和非微扰QCD效应,并做细致的唯象分析。通过对其衰变过程分支比的具体计算,讨论并分析了一些非微扰和 的现象学内容。在本文的绪论部分,作者对相关背景进行了介绍。在第二章,作者对 因子化方法, 介子波函数进行了必要的介绍。在第三、第四章,作者在 因子化方法下给出所探究过程的因子化公式,并做数值计算,对所得理论预言进行了细致的唯象分析。最后,作者对全文做了简短总结和展望。34890 毕业论文关键词: 方法 介子衰变 效应 分支比
Analysis of effects involved in the decays
Abstract: The Large Hadron Collider ( ) at CERN began a new run of higher energy in 2015, and it can produce about enents of meson per year. meson has different characteristics from other heavy quark meson such as D and lighter B mesons. So the studies on its decay processes have great scientific meanings which can not only help us to explore the dynamics of heavy flavor physics,testing the theory of standard model , but also provide to us a good platform to understand the physical properties of the final light scalar mesons.
We adopt the factorization approach to study the two-body charmless non-leptonic decay process, and to explore the perturbative and non-perturbative effects through carefully phenomenological analysis. By the precision calculations for the branching ratio, we explore and analyze some phenomena resulted from the perturbative and non-perturbative effects. In the part of introduction, the author briefly introduces the research background; In the second chapter, the author gives a necessary introduction to the factorization approach and wave functions for the initial meson and the light final states. In the three and four chapter, the author presents the factorization formulas of the considered decay processes in the factorization method and makes the numerical calculations and phenomenological analysis in detail. The involved perturbative and non-perturbative QCD effects in the decays have been discussed. Last, the author summarizes this paper in brief and makes an outlook.
Keywords: approach meson decay effects branching ratio
目录
摘要 ⅰ
Abstract ⅱ
第一章 绪论 1
第二章 因子化方法、理论框架及衰变波函数 3
2.1 因子化方法 3
2.2 基本理论框架 3
2.3 介子波函数 4
第三章 因子化化方法下的解析计算 7
第四章 数值结果与唯象分析 10
4.1 输入参数 10
4.2 数值结果及有关分析 10
第五章 总结与展望 14
致谢 15
参考文献 16