A Unitary and Relativistic Model for $\pi \eta N$ and $\pi \pi N$ Photoproduction

We investigate $\pi \eta N$ photoproduction by using a unitary and relativistic model based on the effective Lagrangian approach. 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. The approach we present here has also been used to investigate $\pi \pi N$ photoproduction. A comparison of our calculation to an existing $\pi \pi N$ photoproduction study is made, and shown to produce consistent results. This agreement convinces us that our ongoing study of $\pi \eta N$ photoproduction will produce similar interesting results.