Photoproduction of pentaquark cascades from nucleons

Abstract

The cross sections for production of pentaquark ${\Xi }_5^{+}$ from the reaction $\gamma p\to K^0{K}^0{\Xi }_5^{+}$ and ${\Xi }_5^{--}$ from the reaction $\gamma n\to K^{+}{K}^{+}{\Xi }_5^{--}$ are evaluated in a hadronic model that includes their couplings to both $\Sigma \bar{K}$ and $\Sigma {\bar{K}}^{\ast }$. With these coupling constants determined from the empirical $\pi NN(1710)$ and $\rho NN(1710)$ coupling constants by assuming that ${\Xi }_5^{+}$, ${\Xi }_5^{--}$, and N(1710) belong to the same antidecuplet of spin 1/2 and positive parity, and using form factors at strong interaction vertices similar to those for pentaquark ${\Theta }^{+}$ production in photonucleon reactions, we obtain a cross section of about 0.03-0.6 nb for the reaction $\gamma p\to K^0{K}^0{\Xi }_5^{+}$ and about 0.1-0.6 nb for the reaction $\gamma n\to K^{+}{K}^{+}{\Xi }_5^{--}$ at photon energy $E_{\gamma }=4.5$ GeV, depending on the value of the coupling constant $g_{K^{\ast }\Sigma {\Xi }_5}$.

Comments: 14 pages, 5 figures