Evidence for the positive-strangeness pentaquark ${\Theta }^{+}$ in photoproduction with the SAPHIR detector at ELSA

The SAPHIR Collaboration, J. Barth

The positive--strangeness baryon resonance ${\Theta }^{+}$ is observed in photoproduction of the $\mathrm{n}{\mathrm{K}}^{+}{\mathrm{K}}_{\mathrm{s}}^0$ final state with the SAPHIR detector at the Bonn ELectron Stretcher Accelerat…