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arXiv · 1304.7975

The role of vector-baryon channels and resonances in the $γp \to K^0 Σ^+$ and $γn \to K^0 Σ^0$ reactions near the $K^* Λ$ threshold

A. Ramos·E. Oset
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Abstract

We have studied the $γp \to K^0 Σ^+$ reaction in the energy region around the $K^* Λ$ and $K^* Σ$ thresholds, where the CBELSA/TAPS cross section shows a sudden drop and the differential cross section experiences a transition from a forward-peaked distribution to a flat one. Our coupled channel model incorporates the dynamics of the vector meson-baryon interaction which is obtained from the hidden gauge formalism. We find that the cross section in this energy region results from a delicate interference between amplitudes having $K^* Λ$ and $K^*Σ$ intermediate states. The sharp downfall is dictated by the presence of a nearby $N^*$ resonance produced by our model, a feature that we have employed to predict its properties. We also show results for the complementary $γn \to K^0 Σ^0$ reaction, the measurement of which would test the mechanism proposed in this work.

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A. Ramos, E. Oset. 2013-11-06. The role of vector-baryon channels and resonances in the $γp \to K^0 Σ^+$ and $γn \to K^0 Σ^0$ reactions near the $K^* Λ$ threshold. https://doi.org/10.1016/j.physletb.2013.10.012

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