2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/126009Revised analysis of $Σ$ beam asymmetry for $η$ photoproduction on the free proton reveals a resonant structure at $W\sim 1.69$ GeV. Comparison of experimental data with multipole decomposition based on the E429 solution of the SAID partial wave analysis and including narrow states, suggests a narrow ($Γ\leq 15$ MeV) resonance. Possible candidates are $P_{11}$, $P_{13}$, or $D_{13}$ resonances. The result is considered in conjunction with the recent evidence for a bump-like structure at $W\sim 1.67 - 1.68$ GeV in quasi-free $η$ photoproduction on the neutron.5 pages, 4 figuresHigh Energy Physics - ExperimentHigh Energy Physics - PhenomenologyNuclear Experimenttext