Feynman diagram: sides switched

Question

In my t-channel Feynman diagram (with tikz-Feynman), the lower two particles of the t-channel are switched. It appears that for s-channel, the right hand side particles are switched too.

Code for t-channel:

\documentclass[a4paper]{article}
 \usepackage{physics}
 \usepackage{graphicx}
 \usepackage[compat=1.1.0]{tikz-feynman}

\begin{document}

t-channel 
\[\feynmandiagram [large, vertical=a to b] {
    i1 [particle=\(\nu\)] -- [fermion, momentum=\(q\)] a -- [boson, momentum=\(k\)] f1 [particle=\(W^+\)],
    a -- [fermion, momentum=\(p\)] b,
    i2 [particle=\(\bar\nu\)] -- [anti fermion, momentum=\(q'\)] b,
    b -- [boson, momentum=\(k'\)] f2 [particle=\(W^-\)],
    };
\]

\end{document}

Expected output:

Got:

How can this be fixed?

Answer 1

You just need to switch the order of the lower two particles.

\[\feynmandiagram [large, vertical=a to b] {
    i1 [particle=\(\nu\)] -- [fermion, momentum=\(q\)] a -- [boson, momentum=\(k\)] f1 [particle=\(W^+\)],
    a -- [fermion, momentum=\(p\)] b,
    b -- [boson, momentum=\(k'\)] f2 [particle=\(W^-\)],
    i2 [particle=\(\bar\nu\)] -- [anti fermion, momentum=\(q'\)] b,
    };
\]