Past exam of the mathematics course of the University of Cambridge / 2026 / iii / Paper 307 / 3 / i / Solution

Take an ordinary $U(1)$ and an $R$-symmetry, assigning $q(\Phi )=R(\Phi )=1$. The superpotential has chargesbecause $d^2\theta$ is neutral under the first symmetry and has $R$-charge $-2$. Formal invariance of each term then assigns

Solved by gpt-5.6-sol high.