% !TEX program = pdflatexmk
% !TEX parameter = -shell-escape
% Author: Izaak Neutelings (December 24)
% Instructions: To compile via command line, run the following twice
%   pdflatex -shell-escape extract/ttbarV$TAG.tex
\documentclass[11pt,border=4pt]{standalone}
\usepackage{feynmp-auto}
\begin{document}
\begin{fmffile}{feyngraph}
  \fmfframe(1,12)(6,15){ % padding (L,T)(R,B)
  \begin{fmfgraph*}(100,75) % dimensions (WH)
    % line style
    \fmfset{wiggly_len}{12} % boson wavelength
    \fmfset{wiggly_slope}{65} % boson slope of waves
    % external vertices
    \fmfstraight
    \fmfleft{i2,i1}
    \fmfright{o3,o2,o1}
    \fmfshift{20 left}{o3}
    % internal vertices (exact placement)
    \fmfforce{(.33w,.75h)}{v1} % exact placement
    \fmfforce{(.33w,.25h)}{v2} % exact placement
    \fmfforce{(.72w,.75h)}{g} % exact placement
    % main
    \fmf{fermion}{i1,v1,v2,i2}
    \fmf{gluon}{g,v1}
    \fmf{fermion}{o2,g,o1}
    \fmf{boson}{v2,o3}
    % labels
    \fmfv{l.d=5,l.a=155,l=$q$}{i1}
    \fmfv{l.d=4,l.a=-150,l=$\overline{q}$}{i2}
    \fmfv{l.d=6,l.a=22,l=t}{o1}
    \fmfv{l.d=6,l.a=-20,l=$\overline{\mathrm{t}}$}{o2}
    \fmfv{l.d=5,l.a=-20,l=Z}{o3}
  \end{fmfgraph*}
  } % close \fmfframe
\end{fmffile}
\end{document}