We analyze the $\gamma p\to {\eta }^{\prime }p$ process within the framework of an isobar model. This model works well in energies from the process threshold $W_{\mathrm{thr}}=1.897\text{GeV}$ up to approximately $2.4\text{GeV}$, which is why we focus on the description of this region only. We construct the amplitude as a sum of tree-level Feynman diagrams with exchanges of proton and nucleon resonances in the $s$ and $u$ channels and $\rho$ and $\omega$ mesons in the $t$ channel. We include also the contact current in order to make the total amplitude gauge invariant. The free parameters of our models were fitted to data on differential cross section and photon-beam asymmetry. We identified the $N\left(1875\right)3/2^{-}, N\left(1895\right)1/2^{-}, N\left(1900\right)3/2^{+}, N\left(2100\right)1/2^{+}$, and $N\left(2120\right)3/2^{-}$ states as the most important ones to get a good description of data. The exchanges of spin-3/2 fields were introduced in the consistent formalism. We show three different models: in two of them we assume pseudoscalar coupling in the strong vertex (one is fitted on cross sections only, the other one is fitted on all data), and in the third model we include the pseudovector coupling in the strong vertex but the data prefer the pseudoscalar coupling as it leads to lower ${\chi }^2$. We compare our models with data and comment on the roles of individual resonances for reliable data description. We give also predictions for the recoil-proton polarization asymmetry and target polarization asymmetry.

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• Particle interactions
• Particle production
• Photonuclear reactions