%
% Complicated Feynman graph
%
% Comment in the lines from \documentclass to \begin{document}
% and from \write18 to \end{document}
% to use the standalone package for testing the Feynman graphs
% You should also change the fmffile name to tree-mp
% \documentclass{standalone}

% \usepackage{feynmp}
% \DeclareGraphicsRule{*}{mps}{*}{}

% \unitlength=1mm
% \begin{document}
\begin{fmffile}{tree}
\begin{fmfgraph*}(50,30)
  \fmfleftn{i}{2} \fmfrightn{o}{4}
  \fmflabel{$e_-$}{i1}\fmflabel{$e_+$}{i2}
  \fmflabel{$\mu_+$}{o1}
  \fmflabel{$\nu_{\mu}$}{o2}
  \fmflabel{$s$}{o3}
  \fmflabel{$\noexpand\bar c$}{o4}
  \fmf{fermion}{i1,v1,i2}
  \fmf{boson,label=$\gamma,,Z$}{v1,v2}
  \fmf{boson}{v3,v2,v4}
  \fmf{fermion}{o1,v3,o2}
  \fmf{fermion}{o4,v4,o3}
  \fmfdot{v1,v3,v4}\fmfblob{.12w}{v2}
\end{fmfgraph*}
\end{fmffile}
% Include this command for Metapost
% \write18{mpost tree-mp}
% \end{document}
