论文标题
任意$ n $ body阶段空间的图形方法
Graphic Method for Arbitrary $n$-body Phase Space
论文作者
论文摘要
在量子场理论中，相空间集成是横截面和衰减宽度的所有理论计算中的重要组成部分。计算物理振幅的虚构部分也需要。一个关键问题是根据$ n $ body系统中任何选择的不变质量表示相位空间公式。我们提出了一种图形方法，以快速获取任何给定的不变质量的相位空间公式，以直观地使用$ n $ d $ d $维时空的任意$ n $ body系统，并在任何参考框架中具有涉及的动量。该方法还大大简化了相位空间的计算，就像Feynman图在计算散射幅度中所做的那样。
In quantum field theory, the phase space integration is an essential part in all theoretical calculations of cross sections and decay widths. It is also needed for computing the imaginary part of a physical amplitude. A key problem is to get the phase space formula expressed in terms of any chosen invariant masses in an $n$-body system. We propose a graphic method to quickly get the phase space formula of any given invariant masses intuitively for an arbitrary $n$-body system in general $D$-dimensional spacetime, with the involved momenta in any reference frame. The method also greatly simplifies the phase space calculation just as what Feynman diagrams do in calculating scattering amplitudes.
