% !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/VLQ_VLL$TAG.tex
\documentclass[11pt,border=4pt]{standalone}
\usepackage{feynmp-auto}
\usepackage{xcolor}
\usepackage{scalerel}
\newcommand{\mylbrace}[2]{\vspace{#2pt}\hspace{4pt}\scaleleftright[\dimexpr6pt+#1\dimexpr0.11pt]{\lbrace}{\rule[\dimexpr2pt-#1\dimexpr0.5pt]{-4pt}{#1pt}}{.}}
\newcommand{\myrbrace}[2]{\vspace{#2pt}\scaleleftright[\dimexpr6pt+#1\dimexpr0.11pt]{.}{\rule[\dimexpr2pt-#1\dimexpr0.5pt]{-4pt}{#1pt}}{\rbrace}\hspace{2pt}}
\definecolor{colVLQ}{rgb}{.5,0,.7} % VLQ (purple)
\begin{document}
\begin{fmffile}{feyngraph}
  \fmfframe(-10,12)(23,11){ % padding (L,T)(R,B)
  \begin{fmfgraph*}(130,85) % canvas (W,H)
    % line style
    \fmfset{wiggly_len}{12} % boson wavelength
    \fmfset{wiggly_slope}{65} % boson slope of waves
    \fmfleft{i2,i1}
    \fmfright{o3,o2,o1}
    % main
    \fmf{fermion}{i1,v1}
    \fmf{fermion}{v1,o1}
    \fmf{gluon}{i2,v2}
    \fmf{fermion}{o3,v2}
    \fmf{fermion,t=1}{v2,v} % t-channel
    \fmf{boson,t=1,l.s=left,l.d=5,label=W/Z}{v,v1} % t-channel
    \fmffreeze
    \fmf{fermion,f=(.5,,0,,.7)}{v,o2} % top out
    % labels
    \fmfv{l.d=6,l.a=160,l=q}{i1}
    \fmfv{l.d=6,l.a=-160,l=g}{i2}
    \fmfv{l.d=6,l.a=22,l=q$'$/q}{o1}
    \fmfv{l.d=6,l.a=0,l=\color{colVLQ} T/B}{o2}
    \fmfv{l.d=6,l.a=-20,l=$\overline{\mathrm{b}}$}{o3}
  \end{fmfgraph*}
  } % close \fmfframe
\end{fmffile}
\end{document}