We describe a model of $\pi \eta N$ photoproduction based on a phenomenological Lagrangian approach that satisfies two-body unitary and is relativistic. Unitarity is ensured by using the Lippmann-Schwinger equation to iterate the vertices and dress the propagators to all orders, and by including all possible two-body and quasi-two-body intermediate channels. This model has been tested by investigating $\pi \pi N$ photoproduction. A preliminary comparison of our calculation to an existing $\pi \pi N$ photoproduction study is made, and is shown to produce consistent results. We have also calculated the sum of the nonresonant Born diagrams in $\pi \eta N$ photoproduction and compared the resulting observables to invariant mass distributions from the CB-ELSA collaboration.
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