Pentaquark Theta(+) production from the reaction gamma p ->pi K-+(-)Theta(+) Academic Article uri icon


  • The cross section for [Formula Presented] production from the reaction [Formula Presented], which was observed in the CLAS experiment at the Jefferson National Laboratory, is evaluated in a hadronic model that includes couplings of [Formula Presented] to both [Formula Presented] and [Formula Presented]. With their coupling constants determined from the empirical [Formula Presented] and [Formula Presented] coupling constants using the SU(3) symmetry, the cross section for this reaction has been evaluated by taking [Formula Presented] to have spin 1/2 and isospin 0 but either positive or negative parity. We find that if [Formula Presented] has positive parity as predicted by the chiral soliton model and the correlated quark model, the cross section is [Formula Presented], depending on the value of the [Formula Presented] coupling. The cross section is reduced by more than a factor of 10 if [Formula Presented] 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 [Formula Presented]-channel kaon-exchange diagram that involves only the coupling of [Formula Presented] to [Formula Presented]. After decreasing with increasing negative four-momentum transfer, the differential cross section increases again when the [Formula Presented]-channel contribution due to intermediate [Formula Presented] propagation becomes important at large negative four-momentum transfer. 2004 The American Physical Society.

published proceedings


author list (cited authors)

  • Liu, W., Ko, C. M., & Kubarovsky, V.

citation count

  • 22

complete list of authors

  • Liu, W||Ko, CM||Kubarovsky, V

publication date

  • February 2004