Abstract
We investigate the photoproduction of the on a nucleon and the pion-induced production reaction on the proton The total cross sections near threshold are estimated by using hadronic models with effective interaction Lagrangians and form factors that preserve the gauge invariance of the electromagnetic current. The photoproduction cross sections are found to be a few hundred nb, with the cross section on the proton being larger than that on the neutron. The pion-induced production cross section is found to be around a few hundred but sensitive to the coupling whose value is not yet known. We also study the production cross section assuming that has negative parity. The cross sections are then found to be very suppressed compared to the case where has positive parity. Hence, the interpretation of the as an odd-parity pentaquark state seems to be disfavored from the estimates of the cross section for the photon-proton reaction from the SAPHIR experiment.
- Received 1 October 2003
DOI:https://doi.org/10.1103/PhysRevD.69.014009
©2004 American Physical Society