Nucleon resonance production in the $\gamma p\to p\eta \varphi$ reaction

In this work, we perform a study of nucleon resonance production in the $\gamma p\to p\eta \varphi$ reaction within an effective Lagrangian approach. In our model, we consider the excitation of the $N^{\ast }(1535)$, $N^{\ast }(1650)$, $N^{\ast }(1710)$ and $N^{\ast }(1720)$ in the intermediate state and the background term. We find that this reaction is dominated by the excitation of the $N^{\ast }(1535)$ in the near threshold region. Especially, we study the possible role of the scalar meson exchange in this reaction. It is found that the $f_0(980)$ exchange may give a significant contribution and the parity asymmetry can be used to identify its role in this reaction.