We analyze the $\gamma p\to K^0{\mathrm{\Sigma }}^{+}$ process in the resonance region within the framework of the isobar model. The amplitude is constructed as a sum of tree-level Feynman diagrams with the addition of the contact current ensuring gauge invariance of the total amplitude. The resonance content of our models is inspired by a model for the isospin-related $K^{+}{\mathrm{\Sigma }}^0$ channel. The main coupling constant in the $K\mathrm{\Sigma }N$ vertex is estimated with the help of isospin symmetry, and the rest of the free parameters (resonance couplings and hadronic form-factor cutoffs) are calibrated to the available $K^0{\mathrm{\Sigma }}^{+}$ data. Using the resulting models, we calculate the differential and total cross sections as well as polarization observables $(P$, $\mathrm{\Sigma }$, $T$, $O_x$, $O_z)$, and compare them with measurements. We identify the $N\left(1720\right)3/2^{+}$ and $N\left(1900\right)3/2^{+}$ states as the most important ones for good correspondence with the experimental data.

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• Effective field theory
• Feynman diagrams
• Particle interactions
• Photonuclear reactions
• Baryons
• Strange quark
• Form factors