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The BGO-OD experiment at the ELSA accelerator facility uses an energy tagged bremsstrahlung photon beam to investigate the excitation structure of the nucleon. The setup consists of a highly segmented BGO calorimeter surrounding the target, with a particle tracking magnetic spectrometer at forward angles. BGO-OD is ideal for investigating low momentum transfer processes due to the acceptance and high momentum resolution at forward angles. In particular, this enables the investigation of strangeness photoproduction where t-channel exchange mechanisms play an important role. This also allows access to low momentum exchange kinematics where extended, molecular structure may manifest in reaction mechanisms. First key results at low t indicate a cusp-like structure in K + Σ 0 photoproduction at W = 1900 MeV, line shapes and differential cross sections for K + Λ(1405)→ K + Σ 0 π 0 , and a peak structure in K 0 S Σ 0 photoproduction. The peak in the K 0 S Σ 0 channel appears consistent with meson-baryon generated states, where equivalent models have been used to describe the P C pentaquark candidates in the heavy charmed quark sector. 

Baryon spectroscopy is an essential tool in the study of nucleon resonances. The use of polarization observables can greatly clarify the spectrum of broad and overlapping nucleon excitations. The N * program with the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility includes experimental studies with linearly- and circularly-polarized tagged-photon beams, longitudinally- and transversely-polarized nucleon targets, and recoil polarizations. An overview of these experimental studies and recent results are presented. 

Since the discovery of the Λ(1405), it remains poorly described by conventional constituent quark models, and it is a candidate for having an “exotic” meson-baryon or “penta-quark” structure, similar to states recently reported in the hidden charm sector. The Λ(1405) can be produced in the reaction γp K + Λ(1405). The pure I=0 decay mode into Σ 0 π 0 is prohibited for the mass-overlapping Σ(1385). Combining a large aperture forward magnetic spectrometer and a central BGO crystal calorimeter, the BGO-OD experiment is ideally suited to measure this decay with the K + in the forward direction. Preliminary results are presented. *Supported by DFG (PN 388979758, 405882627)