Nucleon Resonances in $$\varvec{\gamma p \rightarrow K^{*+} \Lambda }$$

Abstract

We use an effective Lagrangian approach in the tree-level approximation to analyze the high-precision cross-section data for $$\gamma p \rightarrow K^{*+}\Lambda $$ reported by the CLAS Collaboration. Apart from the t-channel K, $$\kappa $$ , $$K^*$$ exchanges, the s-channel nucleon (N) exchange, the u-channel $$\Lambda $$ , $$\Sigma $$ , $$\Sigma ^*(1385)$$ exchanges, and the generalized contact current, we found that at least two nucleon resonances ( $$N^*$$ ’s) should be considered to well describe the high-precision cross-section data. One is the $$N(2060){5/2}^-$$ that is responsible for the shape of the angular distribution near the $$K^*\Lambda $$ threshold via its interference with the t-channel K exchange, and the other could be one of the $$N(2000){5/2}^+$$ , $$N(2040){3/2}^+$$ , $$N(2100){1/2}^+$$ , $$N(2120){3/2}^-$$ and $$N(2190){7/2}^-$$ . The results for $$\Sigma $$ , T and P are predicated and it is pointed out that more data on these observables are needed to further pin down the resonance contents and their associated parameters in this reaction.