Combined analysis of eta' production reactions: gamma N -> eta' N, N N -> N N eta', and pi N -> eta' N

Understand

The production of eta' mesons in photon- and hadron-induced reactions has been revisited in view of the recent additions of high-precision data to the world data base.

• Based on an effective Lagrangian approach, we have performed a combined analysis of the free and quasi-free gamma N -> eta' N, N N -> N N eta', and pi N -> eta' N reactions.
• Considering spin-1/2 and -3/2 resonances, we found that a set of above-threshold resonances {S_{11}, P_{11}, P_{13}}, with fitted mass values of about M_R=1925, 2130, and 2050 MeV, respectively, and the four-star sub-threshold P_{13}(1720) resonance reproduce best all existing data for the eta' production processes in the resonance-energy region considered in this work.
• All three above-threshold resonances found in the present analysis are essential and indispensable for the good quality of the present fits.