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关于费曼图中标签设置的问题

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关于费曼图中标签设置的问题

我想画一个费曼图，为此我编写了这个代码。

\documentclass[a4paper,12pt, border=5mm]{standalone}
\usepackage{tikz}
\usetikzlibrary{decorations, decorations.markings, decorations.pathmorphing, arrows, graphs, graphdrawing, shapes.geometric, snakes}
\usegdlibrary{trees,force, layered}

\pgfdeclaredecoration{complete sines}{initial}
{
    \state{initial}[
        width=+0pt,
        next state=sine,
        persistent precomputation={\pgfmathsetmacro\matchinglength{
            \pgfdecoratedinputsegmentlength / int(\pgfdecoratedinputsegmentlength/\pgfdecorationsegmentlength)}
            \setlength{\pgfdecorationsegmentlength}{\matchinglength pt}
        }] {}
    \state{sine}[width=\pgfdecorationsegmentlength]{
        \pgfpathsine{\pgfpoint{0.25\pgfdecorationsegmentlength}{0.5\pgfdecorationsegmentamplitude}}
        \pgfpathcosine{\pgfpoint{0.25\pgfdecorationsegmentlength}{-0.5\pgfdecorationsegmentamplitude}}
        \pgfpathsine{\pgfpoint{0.25\pgfdecorationsegmentlength}{-0.5\pgfdecorationsegmentamplitude}}
        \pgfpathcosine{\pgfpoint{0.25\pgfdecorationsegmentlength}{0.5\pgfdecorationsegmentamplitude}}
}
    \state{final}{}
}

\tikzset{
    photon/.style={
        decoration={complete sines, amplitude=0.15cm, segment length=0.2cm},
        decorate    
    },
    fermion/.style={
        decoration={
            markings,
            mark=at position 0.5 with {\node[transform shape, xshift=-0.5mm, fill=black, inner sep=1pt, draw, isosceles triangle]{};}
        },
        postaction=decorate
    },
    gluon/.style={
        decoration={coil, aspect=0.75, mirror, segment length=1.5mm},
        decorate
    }, 
    left/.style={
        bend left=90,
        looseness=1.75
    }
}

\begin{document}%
\begin{tikzpicture}
\graph [spring layout, anchor at={(0,-4)}, nodes=coordinate, vertical= a to d, vertical= e to f]
{
a -- [fermion, edge label={\tiny{$\nu_{\mu/\tau}$}}] b,
c -- [fermion, edge label={{\tiny{$\nu_{\mu/\tau}$}}}] a,
a -- [photon, edge label={\tiny{$Z'$}}] d -- [left, fermion, edge label={\tiny{$\mu^-/\tau^-$}}] e -- [left, fermion, edge label={\tiny{$\mu^-/\tau^-$}}] d,
e -- [photon, edge label={\tiny{$\gamma$}}] f,
g-- [fermion, edge label={\tiny{$p$}}] f,
f -- [fermion, edge label={\tiny{$p$}}] h;
};

\end{tikzpicture}
\end{document}

输出为：

在此处输入图片描述

但是标签看起来不太好，尤其是（如果费米子线的标签看起来像线的标签$\nu_{\mu/\tau}$就更好了）。而且标签的文字大小非常大。$\nu_{\mu/\tau}$$p$

谁能帮我解决这些问题？

答案1

下面是散射事件的简化版本，它从简化的弹簧布局开始：

\feynmandiagram [vertical = c to f] {
    {a,b} -- c -- d -- e -- f -- {g,h};
}

在左边的截图中，我标记了你画的点。右边的截图是由下面的代码生成的。

目前，它只是为了简单起见而删除了箭头。您可以通过拆分结构来处理它们，例如，就像我对缺失的半弧所做的那样。看起来不应该太字面地理解这些术语（费米子、玻色子等），而应该更多地使用它们来获得所需的绘图。这就是为什么我使用“费米子”来表示轻子圆。

编码

\documentclass[10pt, border=10pt]{standalone}

\usepackage{tikz-feynman}

\begin{document}

\feynmandiagram [vertical = c to f] {
%   {a,b} -- c -- d -- e -- f -- {g,h}; % basic structure

    {   a [particle=\(\nu_\mu / \tau\)] ,% R
        b [particle=\(\nu_\mu / \tau\)] % L
    }
    -- c 
    -- [boson, edge label=\(Z^{'}\)] d 
    -- [fermion, half left, edge label=\(\mu^{-}/\tau^{-}\)] e 
    -- [photon, edge label=\(\gamma\)] f 
    -- {g [particle=\(p\)],h [particle=\(p\)]};
    
    % adding the missing half-loop
    e -- [fermion, half left, edge label=\(\mu^{-}/\tau^{-}\)] d;
};


\end{document}

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