% !TEX program = pdflatexmk
% !TEX parameter = -shell-escape
% Author: Izaak Neutelings (September 24)
% Instructions: To compile via command line, run the following twice
%   pdflatex -shell-escape extract/higgs_pair_pp$TAG.tex
\documentclass[11pt,border=4pt]{standalone}
\usepackage{feynmp-auto}
\usepackage{xcolor}
\definecolor{colkappah}{rgb}{0,0,1} % kappa_lambda (blue)
\begin{document}
\begin{fmffile}{feyngraph}
  \fmfframe(6,12)(14,12){ % padding (L,T)(R,B)
  \begin{fmfgraph*}(140,80) % dimensions (WH)
    % line style
    \fmfset{wiggly_len}{12} % boson wavelength
    \fmfset{wiggly_slope}{65} % boson slope of waves
    % external vertices
    \fmfleft{i2,i1}
    \fmfright{o4,o3,o2,o1}
    \fmfshift{12 down}{i1}
    \fmfshift{12 up}{i2}
    \fmfshift{4 up}{o2,o3}
    % main
    \fmf{fermion,t=1.2}{i1,v1,i2}
    \fmf{gluon,t=1.2}{v2,v1}
    \fmf{phantom,t=1.3}{o4,h2,v2,h1,o1}
    \fmffreeze
    \fmf{fermion}{o4,v2,h1,o1}
    \fmf{phantom,t=0.8}{h2,h}
    \fmf{dashes}{h1,h} % Higgs boson
    \fmf{dashes}{o2,h} % Higgs boson
    \fmf{dashes}{o3,h} % Higgs boson
    % Higss coupling
    \fmfv{decor.shape=circle,decor.filled=full,decor.size=4,f=(0,,0,,1),
          l.d=5,l.a=-120,l=\color{colkappah}$\kappa_\lambda$}{h}
    % labels
    \fmfv{l.a=120,l.d=5,l=$q$}{i1}
    \fmfv{l.a=-120,l.d=5,l=$\overline{q}$}{i2}
    \fmfv{l.a=25,l.d=6,l=t}{o1}
    \fmfv{l.a=20,l.d=6,l=\strut h}{o2}
    \fmfv{l.a=-20,l.d=6,l=h}{o3}
    \fmfv{l.a=-20,l.d=6,l=$\overline{\mathrm{t}}$}{o4}
  \end{fmfgraph*}
  } % close \fmfframe
\end{fmffile}
\end{document}