Exploring Structure Constants in Planar $\mathcal{N} = 4$ SYM: From Small Spin to Strong Coupling

Abstract: We study the structure constants of two conformal primary operators and one spinning operator in planar $\mathcal{N} = 4$ Super-Yang-Mills theory using the hexagon formalism. By analytically continuing in the spin, we derive a formula for computing these structure constants at any coupling in the small-spin limit, up to a normalization factor. This formula allows us to explore their analytical properties at strong coupling. In this regime, using classical string calculations and a suitable ansatz, we extend our analysis to finite-spin operators, verifying recent two-loop results for structure constants in string theory and generalizing them to operators with arbitrary R-charges.