I'm doing a row of three Feynman diagrams made with tikz-feynman. I'm having some problems with alignments.
First, I use subcaptionbox to have a vertical alignment of the subcaptions (see here). Second, I use scalebox to make them smaller (see here) so the three fit in the row.
This is the code:
\documentclass[12pt,a4paper]{article}
% LuaLaTeX is used
\usepackage{tikz}
\usepackage{caption}
\usepackage{subcaption}
\usepackage[compat=1.1.0]{tikz-feynman}
\begin{document}
\begin{figure}
\subcaptionbox{The left}{\scalebox{1}{
\begin{tikzpicture}
\begin{feynman}
\vertex (a) {\(g\)};
\vertex[right=1cm of a] (b);
\vertex[below right=1cm of b] (c);
\vertex[below left=1cm of c] (d);
\vertex[left=1cm of d] (e) {\(g\)};
\vertex[right=1cm of b] (f) {\(t\)};
\vertex[right=1cm of c] (g) {\(H\)};
\vertex[right=1cm of d] (h) {\(\overline{t}\)};
\diagram*{
(a) -- [gluon] (b),
(b) -- [anti fermion] (c),
(c) -- [anti fermion] (d),
(d) -- [gluon] (e),
(b) -- [fermion] (f),
(c) -- [scalar] (g),
(d) -- [anti fermion] (h),
};
\end{feynman}
\end{tikzpicture}
}}
\hfill
\subcaptionbox{The left}{\scalebox{1}{
\begin{tikzpicture}
\begin{feynman}
\vertex (a) {\(g\)};
\vertex[below right=1cm of a] (b);
\vertex[below left=1cm of b] (c) {\(g\)};
\vertex[right=1cm of b] (d);
\vertex[above right=1cm of d] (e);
\vertex[below right=1cm of d] (f) {\(\overline{t}\)};
\vertex[above right=1cm of e] (g) {\(t\)};
\vertex[below right=1cm of e] (h) {\(H\)};
\diagram*{
(a) -- [gluon] (b),
(c) -- [gluon] (b),
(b) -- [gluon, edge label=\(g\)] (d),
(d) -- [fermion, edge label=\(t\)] (e),
(d) -- [anti fermion] (f),
(e) -- [fermion] (g),
(e) -- [scalar] (h),
};
\end{feynman}
\end{tikzpicture}
}}
\hfill
\subcaptionbox{The left}{\scalebox{1}{
\begin{tikzpicture}
\begin{feynman}
\vertex (a) {\(q\)};
\vertex[below right=1cm of a] (b);
\vertex[below left=1cm of b] (c) {\(\overline{q}\)};
\vertex[right=1cm of b] (d);
\vertex[above right=1cm of d] (e);
\vertex[below right=1cm of d] (f) {\(\overline{t}\)};
\vertex[above right=1cm of e] (g) {\(t\)};
\vertex[below right=1cm of e] (h) {\(H\)};
\diagram*{
(a) -- [fermion] (b),
(c) -- [anti fermion] (b),
(b) -- [gluon, edge label=\(g\)] (d),
(d) -- [fermion, edge label=\(t\)] (e),
(d) -- [anti fermion] (f),
(e) -- [fermion] (g),
(e) -- [scalar] (h),
};
\end{feynman}
\end{tikzpicture}
}}
\caption{Feynman diagrams.}
\end{figure}
\end{document}
Here is the output:
I need the three diagrams to be vertically aligned. I searched some solutions, but still I don't know how to solve this.



subcaptions \ 2) subcaptions are not aligned (you can check with\underline) (this is why I used\subcaptionboxat first) – Abel Gutiérrez May 02 '22 at 08:38Labels cannot be used with these "sub-captions". This is usually not a problem, since the comparison or explanation of the subfigures is done in the main caption of the figure and not later in the text. Even so the reference will be the full figure.
– Simon Dispa May 02 '22 at 13:49