Field-Theoretic Reggeization in Five- and Six-Point Functions

Multiparticle $S$-matrix elements of the type $N\gamma \to N\gamma \gamma$, $N\gamma \gamma \to N\gamma \gamma$ are calculated in the tree approximation, in a field theory of spin-½ "nucleons" ($N$) and spin -1 massive "photons" ($\gamma$) coupled to the conserved nucleon current. After projecting out the positive-parity amplitude, the asymptotic behavior is found to be consistent with a Reggeized nucleon. The double-Reggepole limit of $N\gamma \to N\gamma \gamma$ also indicates a Reggeized nucleon, and the residues factor. The method can be extended to $S$-matrix elements with arbitrary numbers of photons.