Pentaquark + production from the reaction p+K-+

The cross section for + production from the reaction p+K-+, which was observed in the CLAS experiment at the Jefferson National Laboratory, is evaluated in a hadronic model that includes couplings of + to both KN and K*N. With their coupling constants determined from the empirical NN(1710) and NN(1710) coupling constants using the SU(3) symmetry, the cross section for this reaction has been evaluated by taking + to have spin 1/2 and isospin 0 but either positive or negative parity. We find that if + has positive parity as predicted by the chiral soliton model and the correlated quark model, the cross section is 50-110 nb, depending on the value of the K*N coupling. The cross section is reduced by more than a factor of 10 if + has negative parity as given by lattice QCD studies and the uncorrelated quark model. For both parities, the differential cross section peaks at small negative four-momentum transfer when the reaction is dominated by the t-channel kaon-exchange diagram that involves only the coupling of + to KN. After decreasing with increasing negative four-momentum transfer, the differential cross section increases again when the u-channel contribution due to intermediate + propagation becomes important at large negative four-momentum transfer.

Pentaquark ⁺ production from the reaction p⁺K^-⁺ Academic Article