= Wess–Zumino spurion charge assignment
{c}
{title2=$q(\Phi,m,g)=(1,-2,-3),\quad R(\Phi,m,g)=(1,0,-1)$}
For quadratic and cubic interactions, assigning the couplings chiral <spurion> transformations makes each monomial formally covariant. The ordinary $U(1)$ leaves $\theta$ neutral, while the <R-symmetry> gives it charge one and the <superpotential> charge two. The neutral ratio $g\Phi/m$ and the covariant factor $m\Phi^2$ give the symmetry-allowed holomorphic form $m\Phi^2f(g\Phi/m)$. Perturbative regularity and tree matching are additionally needed for <superpotential non-renormalization>; symmetry alone leaves an arbitrary function. Fixed numerical couplings need not enjoy these formal symmetries as actual field symmetries.
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