New cross sections for the reaction $\mathrm{ep}\to \mathrm{ep}\eta$ are reported for total center of mass energy $W=1.5\mathrm{}–1.86\mathrm{GeV}$ and invariant momentum transfer $Q^2=0.25\mathrm{}–1.5(\mathrm{GeV}/c{)}^2$. This large kinematic range allows extraction of important new information about response functions, photocouplings, and $\eta N$ coupling strengths of baryon resonances. Newly observed structure at $W\sim 1.65\mathrm{GeV}$ is shown to come from interference between $S$ and $P$ waves and can be interpreted with known resonances. Improved values are derived for the photon coupling amplitude for the $S_{11}\left(1535\right)$ resonance.

• Received 8 November 2000

DOI:https://doi.org/10.1103/PhysRevLett.86.1702