Photoproduction of η -mesons on the deuteron above S11(1535) in the presence of a narrow P11(1670) -resonance

Incoherent photoproduction of η -mesons on the deuteron is considered. The main attention is paid to the region above the S 11(1535) -resonance where a rather narrow resonance-like structure in the total cross-section extracted for γn → ηn has been reported. The corresponding experimental results are analyzed from the phenomenological standpoint within the model containing a baryon P11 with a mass of about 1670MeV and a width less than 30MeV. This resonance was suggested in some recent works as a nonstrange member of the pentaquark antidecuplet with J P = 1/2+ . The calculation is also performed for the polarized and unpolarized angular distributions of η -mesons. In addition, we present our predictions for the cross-sections of the neutral kaons and double pion photoproduction, where the same narrow P 11(1670) -resonance is assumed to contribute through the decay into K 0Λ and πΔ configuration.